How to Compare Specificity, Build Concepts, and Change Theory: A Creative Methodology to Grasp Urbanization Processes

Abstract: In a range of comparative methods that have emerged in recent years, scholars were increasingly drawing on innovative approaches to engage with today's diverse and complex urban worlds. Yet few researchers to date—in the field of urban studies or in spatial disciplines in general—have focused on the design and implementation of comparative inquiry. With this article, I seek to contribute to these current debates by presenting the specific methodology developed in the framework of the research project Patterns and Pathways of Planetary Urbanization. The main questions are: How can the spatiality of large urban territories be empirically studied? How can urbanization processes be analyzed comparatively? To tackle these questions, I focus on our experiences of putting the comparative procedure to work, drawing on a complementary set of ethnographic, cartographic, and historiographic methods useful for a creative, transdisciplinary, and more collaborative study of urbanization. I conclude with a call for a broad discussion of methodology and its theoretical implications by emphasizing the intrinsic link between crafting new methods and the generation of comparative concepts.

Key words: comparative urbanism; planetary urbanization; ethnography; mapping; historiographic approach; collaborative research; grounded theory methodology; transductive approach

3.3 Advancing regressive-progressive methods for a comparative historical analysis

4.1 First comparative moment: Identifying different urbanization processes for each case study

4.2 Second comparative moment: Identifying urbanization processes across case studies

Advancing research methods and methodology to engage with today's diverse and complex urban worlds is key to comparative inquiry. Scholars working across different case studies are confronted with particular challenges that invite them to revisit, rethink, and add to conventional methods and modes of research (e.g., GOUGH, 2012; WARD, 2010; ROBINSON, 2011, 2016; SÖDERSTRÖM, 2013). Authors of two recent FQS thematic issues contributed to these current debates. In the first issue, they emphasized the methodological challenges of cross-cultural comparison, suggesting how established methodologies and research designs can be adapted in order to analyze spatial transformations (BAUR, MENNELL & MILLION, 2021). In the second issue, authors reflected on researchers' practices of comparison while accounting for different disciplines and diverging epistemic cultures (BAUR, CASTILLO ULLOA, MENNELL & MILLION, 2021). Moreover, scholars engaging with theoretical interventions like planetary urbanization (BRENNER & SCHMID, 2011, 2015; SCHMID, 2018) and the critique of methodological cityism (ANGELO & WACHSMUTH, 2015) as well as the postcolonial conceptualization of ordinary cities (ROBINSON, 2006) called for methodological innovations in understanding urbanization. In these current approaches, scholars emphasized that visionary methods are not only needed for a theoretical understanding of urbanization, but also for provincializing or decentering theory production (e.g., LEITNER & SHEPPARD, 2016; MYERS, 2014; REN & LUGER, 2015). [1]

In this article, I do not claim that comparative endeavors are entirely new or that various researchers—particularly those from disciplines like social anthropology and sociology—have failed to discuss the potential and limits of comparison over the last two decades (e.g., CANDEA, 2018; DEVILLE, GUGGENHEIN & HRDLIČKOVÁ, 2016; FOX & GINGRICH, 2002; NIEWÖHNER & SCHEFFER, 2010; YENGOYAN, 2010). While rejecting older, universalist comparative methods, these scholars presented new approaches that are especially relevant for understanding the urbanized planet of the twenty-first century. In fully acknowledging the long and varied trajectory of comparative inquiries in social sciences at large, I specifically explore innovative approaches to comparison in the field of urban studies, and I hope to encourage a more transdisciplinary dialogue about comparative research. [2]

In urban studies, a variety of different comparative methods for which scholars drew on less traditional and more creative approaches have emerged in recent years (e.g., BRILL, 2022; ROBINSON, 2011, 2022a). Yet, only a few researchers focused on the methodological design of such innovative comparative studies by showing, for example, how retrospectively comparing radically different urban contexts can provide both specific insights and generalizations of the urban (LANCIONE & McFARLANE, 2016), or how, if applied in a more sequential and recursive manner during the development of both cases, comparing supposedly incomparable cases can lead to conceptual innovation (TEO, 2022). Furthermore, other researchers demonstrated that tracing is a useful means of comparing cities and providing a conceptual framework for policy research (WOOD, 2020); and still others showed how an inductive approach not only enabled them to detect similarities and differences among cases but forced them to reconsider what they learned from other experiences (BRILL, 2021). However, even less explored in current urban studies debates than various comparative methods are the broad theoretical implications of these creative methodological approaches. [3]

With this article, I contribute to current debates in the field of urban studies in particular and spatial disciplines in general by presenting the specific methodology developed in the framework of the research project Patterns and Pathways of Planetary Urbanization, which was carried out at the Future Cities Lab of the National University of Singapore and the Department of Architecture of ETH Zurich, Switzerland, between 2011 and 2017. In this project, the research team analyzed various case studies of large and heterogeneous urban territories empirically with qualitative methods and, along the way, developed a comparative procedure to generate new concepts that help to describe and conceptualize urbanization processes. Going beyond work that has already been published in the framework of the project, in this methodological intervention, I focus on our experiences of putting the comparative procedure to work, drawing on a complementary set of ethnographic, cartographic, and historiographic methods suited for a creative, transdisciplinary, and collaborative study of urbanization. To do this, I ask the following two questions: How can the spatiality of large urban territories be empirically studied? How can urbanization processes be analyzed comparatively? [4]

In our project, we understood urbanization as an ever-changing dynamic social process that continuously establishes, alters, and transforms urban territories. While the concept of urbanization in urban studies could be considered as rather general, concepts of urbanization processes are usually more specific and more narrowly defined insofar as they emphasize the processual and relational character of urbanization. Additionally, we used the term urban configuration to describe a certain moment in time that captures a snapshot of an urbanization process. Accordingly, the characteristics of a specific urban configuration might change over time, and any description of it is always tentative and provisional. We used this term to analytically structure the urban territory in order to be able to better comprehend it (SCHMID, 2023, pp.35-36). When framing and analyzing urbanization processes empirically like this, it became evident, as this article will demonstrate, that methodological approaches do not simply emerge automatically from theoretical assumptions. Rather, methodology and theory were mutually entangled and thus significantly influenced and modified each other (STREULE, 2013, 2018, 2020). If urban theory is to be revised, developing innovative and creative methodologies and rationales for comparative analysis is indispensable, as ROBINSON (2006, 2016, 2022b; see also COLEMAN, 2017; LURY & WAKEFORD, 2012) put it. This creative approach also applies to the nitty-gritty activity of doing comparative research and the kind of methods employed in such a research process.¹⁾ It is thus necessary, as I argue in this article, to simultaneously reflect on the development of new and inventive methods that draw diverse and complex urban contexts into an analytical conversation, to problematize dominant assumptions and parochial imaginaries of urbanization, and to rework urban theory. [5]

The article is organized as follows. Firstly, I give a brief overview of the research project, focusing on the newly developed comparative methodological procedure (Section 2). After that, I retrace the research process step by step, discussing complementary ethnographic, cartographic, and historiographic methods and showing how adopting, combining, and adapting these well-established methods can lead to three consecutive comparative moments (Section 3-4). These moments are crucial both for the analysis of each case study and for generating new concepts of urbanization processes. Finally, I reflect on the intrinsic link between crafting new methods of data collection and analysis and generating comparative concepts before turning to the possible implications of this link for urban studies and cognate disciplines in general (Section 5). [6]

Comparisons of cases across the world have become fashionable in urban studies, and this approach has been practiced and widely discussed for more than a decade. Unique to this research project, however, was the collective approach, the methodological procedure that combines and advances existing methods, and the complexity involved in comparing eight case studies. Needless to say, this does not mean that this is the best way of doing comparisons, but I believe the experience the research team gained during this project offers important insights to scholars and students. The aim of the study was to build theory and generate new concepts by comparing urbanization processes in eight large metropolitan territories across the planet: Tokyo, the East Pearl River Delta (Hong Kong, Shenzhen, and Dongguan), Kolkata, Istanbul, Lagos, Paris, Mexico City, and Los Angeles. The project was based on the concept of planetary urbanization. We, the research team, were interested in understanding specific, everyday urbanization processes (not cities themselves) as well as their transformations at expanding scales and increasing complexity. The project was also built on postcolonial critiques to provide a variety of approaches to urbanization that enabled us to decenter and enrich established urban theory. To achieve this goal, we engaged empirically with places and residents' everyday knowledge, which is usually underrepresented in urban theory. We also examined works conceptualizing urbanization in languages other than English (for an expanded introduction to the project, see SCHMID & STREULE, 2023a; SCHMID et al., 2018). [7]

As in other comparative studies, the research team drew on cases from diverse geographical and historical contexts. The goal of the comparison, however, was not to simply identify similarities and differences among the cases as universalist comparative methods usually do. Rather, like more recent comparative approaches in the social sciences (e.g., CANDEA, 2018; DEVILLE et al., 2016; FOX & GINGRICH, 2002; NIEWÖHNER & SCHEFFER, 2010), we sought to bring different cases into conversation with one another by building analytical connections²⁾ in order to conceptualize specific and empirically grounded definitions of urbanization processes. To make this comparison work, we had to understand the specificity of each case and the conditions under which each urban territory emerged. Hence, the aim was to use comparison to detect and reconstruct new concepts of urbanization that might be related to each other in various ways. As these concepts required a great range of flexibility, we kept their definitions as open as possible. [8]

This open approach was also reflected in our methodology and the methods we applied. As a methodological principle, the urbanization processes to be compared and the criteria for comparison were not pre-given, and we sought to avoid reliance on any kind of predefined concepts (SCHMID et al. 2018, p.32). The new concepts of urbanization processes had to emerge during the research process itself: at each stage of the research process, from data collection to analysis, we used comparison to revise the emerging concepts. This specific methodology is very similar to iterative strategies of grounded theory methodology (GTM; see CHARMAZ, 2014)—yet unlike first generation GTM, we did not follow primarily an inductive approach that rejects a priori theoretical assumptions. Rather, we adopted a transductive approach that involved going back and forth between conceptual and empirical work—as also in later GTM has been suggested.³⁾ In practice this meant, that even though we started from the well-defined theoretical assumption that urbanization is a multi-dimensional social process which produces social space through material interaction, territorial regulation, and everyday experience, we did not simply test the existing theory empirically (as a deductive approach would imply), nor did we begin our field research with a hypothesis about urbanization processes that we expected to observe (as one way of abductive reasoning would do). Rather, it was our transductive approach that led to a theoretically informed, yet open and empirically grounded analysis of urbanization processes, and thus, to our conceptual innovation. As such, this approach resonates strongly with the second way of abduction as discussed for later GTM by BRYANT (2009), CHARMAZ (2014) and REICHERTZ (2007). In this case, abductive thinking enables researchers generating new knowledge linked to data, observations, or other forms of evidence. As BRYANT pointed out this is very close to induction, yet is different because grounded theorists are not interested in a reformulation of what is already known, but work towards theory construction (2009, §94). [9]

Our strategy was made possible only by our collective approach. This involved shaping methods in many ways. Of these, I will highlight only the most crucial: transdisciplinarity and collaborative theorizing. First, the members of the team brought into one shared methodological frame their various disciplinary backgrounds, including geography, sociology, social anthropology, urban planning and architecture, and their, at times, long-standing empirical research experience of a specific case, while, at the same time, allowing the evolving comparison to inform their own research. In other words, we engaged in the comparative procedure from the outset of the study and systematically compared data from one case with data from another.⁴⁾ Among other things, this resulted in several PhD theses in which the authors analyzed some of the case studies and identified various urbanization processes in each dissertation (HANAKATA, 2016, 2020; KOCKELKORN, 2017; SAWYER, 2016; STREULE, 2016, 2018; WONG, 2016). [10]

Second, this collective approach enabled us to move from qualitative inquiry in descriptive studies (as each individual team member did in one case study) to comparative theory-building, and thus to conceptualizing urbanization processes. In this iterative project, the entire research team and occasionally also colleagues outside the project engaged in collaborative theorizing in long and intense debates during regular team workshops. In this way, it was possible to develop about a dozen comparative concepts that captured several common features and dynamics of urbanization processes. We then introduced and further discussed these concepts in a series of coauthored articles (HANAKATA, STREULE, SCHMID, 2022; KARAMAN, SAWYER, SCHMID & WONG, 2020; KOCKELKORN, SCHMID, STREULE &, WONG, 2023; SAWYER, SCHMID, STREULE & KALLENBERGER, 2021; SCHMID et al., 2018; STREULE, KARAMAN, SAWYER & SCHMID, 2020). [11]

A crucial first step in the empirical research was to define the case studies for comparison. To do this, we adopted a generative approach to building conceptual insights by intentionally composing analytical proximities across cases (ROBINSON, 2016). Thus, the selection was not the result of a systematic analysis of certain criteria such as economic structure, demographics, or regional characteristics and the concomitant search for categories of cities, such as "global cities," "metropolitan regions," or "megacities." Rather, our main criterion was to select very large yet diverse urban territories situated across the planet, including those displaying very different economic, social, and political situations and forms of everyday life. Against the backdrop of this open sampling, we selected the eight cases according to a main commonality: population size. All the eight urban territories selected are very large. The smallest, Paris, consists of about twelve million inhabitants, and the largest, the entire Pearl River Delta, has a population of about 60 million. Our sample represents about one-quarter of all urban territories in this range (SCHMID & STREULE, 2023b, p.362). [12]

Many researchers doing comparative studies might select case studies for similar reasons. However, what made our study different from extant approaches was our definition of the units of analysis based on our specific understanding of urbanization. In this way, the geographical frame of analysis of each case study was left open to include the large region extending far beyond the city itself into the interface of concentrated and extended urbanization.⁵⁾ This geographical framing was merely taken as the practical extent of the area under analysis (SCHMID et al. 2018, p.32). After this first approximation, we defined the concrete boundaries of the research units during the multi-sited research process with the aid of interlocutors interviewed at each site and newly developed mapping procedures. I expand on these methods below. For now, I emphasize that the units of analysis were constructed. Here again, the insights of scholars from other social science disciplines and of researchers using non-representational approaches to units of analysis such as the notion of the field in social anthropology increasingly influence current debates in urban studies (see e.g., AMIT, 2000; FALZON, 2009; NAESS, 2016). Put differently, and as I argued elsewhere (STREULE, 2020, pp.427-428), the perimeter that must be defined in order to study urbanization is neither a neutral tool nor a given space, but a theoretically and empirically co-produced relational urban territory that relies on everyday experience as a site of knowing and knowledge production. With this conceptualization in mind, the unit of analysis was itself transformed into a research object that is not delineated by administrative boundaries but is rather defined through local, regional, and global processes. I now describe the implementation and application of the methodological approach in greater detail. [13]

When launching a qualitative study of contemporary urbanization processes and spatial transformations on a metropolitan scale, we were confronted with the challenge of how to study urbanization empirically. As we did not find adequate tools among the conventional social science methods, we developed a creative methodology that allowed for a thorough analysis of concrete local and historical urban contexts. Building on well-established methods in urban studies, such as field research, cartography and historiographic methods, we combined and advanced these existing methods in our unconventional approach to urbanization processes. Furthermore, we organized regular team workshops to compare the preliminary results of the studies. These workshops formed the core of our procedure and were vital in developing the comparative concepts that emerged during the research process itself. The main steps of our research process can be structured analytically by three consecutive comparative moments—identifying different urbanization processes for each case study, identifying and describing urbanization processes across cases in comparative team workshops, and finally, generating concepts through collective writing (see Figure 1).

Figure 1: Diagram of the methodological design to create comparative moments. In practice, the procedure was not as linear as the figure might suggest. Following a transductive approach, a pivotal insight or realization of analytic connections can happen at any time during the research process. Click here to download the PDF file. [14]

While it was invaluable to have a diverse range of disciplines represented in the research team, we also had to adapt our field research to reflect our varied expertise as human geographers, social anthropologists, architects, urban planners, and sociologists. Each researcher used multi-sited strategies, yet the methods applied for this field research ranged from long-term ethnographic studies to a series of short field visits at various times. Moreover, the walking method had to be adjusted to the specific ways of moving on the streets in each case study, where questions of who can move where, how, and when are key (STREULE, 2017; see also GENZ, 2020). Aware of these hurdles, we all drew on participant observations during exploratory walks through the research area, though this basic method was applied in various ways. We also continuously complemented these individual exploratory walks with expert-guided tours through specific urban areas and used different kinds of qualitative interviews, such as expert interviews, narrative interviews, or in-depth interviews conducted during commented walks. I elaborate on this below. The interlocutors and interviewees ranged from everyday users and producers of space, inhabitants, activists, and artists to policy makers, academics, and project developers. The objective of this method was to identify urbanization processes that were dominating certain areas of each case study and to focus on the lived practices and embodied experiences of these diverse actors. Furthermore, we contextualized the findings by means of a comprehensive review of the literature produced by local scholars, archival research, and by consulting the local media. [15]

The variation in field research approaches described here is partly due to the interdisciplinary background of the team, yet this diversity is also mirrored in the individual positionality of each researcher as well as in their different levels of experience in and knowledge of the field (for a critical discussion of ethnographic comparison, see FÄRBER, 2021). Hence, it would be misleading to suggest that there was a uniform approach to the individual case studies or a pre-set methodological strategy for the project. Rather, the method we applied consisted of systematic, yet flexible guidelines for collecting and analyzing qualitative data during field research. This became evident in the case of my study of Mexico City, in which my background as a social anthropologist enabled me to apply this procedure in a more systematic way, as I will now briefly outline (for a more detailed discussion, see STREULE, 2018, 2020, 2023). [16]

My specific methodological design of a mobile ethnography to study the urbanization processes of Mexico City is one example of the various field research strategies used by different team members. Additionally, I use this example to illustrate exchange and mutual learning among team members by showing how the creative approach changed my research and how this exchange in turn informed the comparative project in general. [17]

While we all needed to employ multi-sited strategies for our qualitative study of urbanization processes, each researcher applied the method of field research in a specific way as I outlined above. To use mobile ethnography in my framing as a research tool, I drew on the same range of well-established research techniques as the other team members. However, in my study of urbanization processes in Mexico City, it became evident to me that there are serious limitations to conventional and orthodox applied ethnographic methods (STREULE, 2020, p.428; 2023). One example of these limitations was an exclusive focus on single administrative units such as neighborhoods, as well as the tendency to reject wide-reaching theoretical assumptions about urbanization, including the importance of areas beyond the city center of Mexico City. I thus adopted and adapted ethnographic methods to suit my research question. [18]

In doing so, I developed two complementary strategies, i.e., recorridos explorativos [explorative tours] and entrevistas en movimiento [interviews on the move] to set ethnography in motion. Together they form the basis of a specific methodological design of mobile ethnography that draws on existing scholarship of walking methods (DELGADO, 2007; GARCÍA CANCLINI, 1996; INGOLD & VERGUNST, 2008) and go-along interviews (KUSENBACH, 2003; LEE & INGOLD, 2006; ROHDE & WILDNER, 2020) and adapts them to study large and heterogeneous urban territories. Firstly, with the technique of the recorridos explorativos, I advanced the method of a "floating observation"⁶⁾ (PÉTONNET, 1982; see also DELGADO, 2007) for walking and perceiving urban space on a metropolitan scale.⁷⁾ Secondly, I developed the technique of the entrevistas en movimiento for conducting semi-structured in-depth interviews during commented walks in multi-sited fields.⁸⁾ [19]

Moving in such a complex multi-sited and multi-scalar field, I needed to be open to new questions and issues emerging in the field. This analysis also included distinguishing the main actors who produce a specific urban configuration as well as identifying power relations between and among different groups of interest (see also SCHWARZ & STREULE, 2016, 2022). The goal of the mobile ethnography as framed here was to describe and understand the specifics of a field only insofar as it contributed to the comprehension of urbanization processes.⁹⁾ [20]

This demonstrates the reciprocal influence of the case studies and comparative theorization in the development of innovative methods. In other words, the emphasis on urbanization in the broader research project has profoundly reshaped my own ethnographic approach. By employing this unusual perspective on a metropolitan scale, mobile ethnography as it is framed here offers a way to identify and describe urbanization processes based on grounded, qualitative, and empirical data. The focus of this mobile ethnography was thus not on the description of a specific place or city but on investigating how and why certain urbanization processes are dominant in specific urban areas, how they can be explained, and how they shape urban territories. Hence, my sampling method was aimed at theory construction (known as theoretical sampling in GTM), not representativeness. More broadly, I showed in my study the importance of recalibrating existing ethnographic methods and inventing dynamic and mobilized research strategies that enabled me to follow urbanization processes on the ground at the street level (see also LURY & WAKEFORD, 2012; WILDNER, 2015). I shared and discussed my methodological reflection with the team, and my mobile ethnography became a formative ingredient in the project's original set of methods as well as a model from which my colleagues developed their own specific and situated field research methods. [21]

Mapping was a key comparative tool, as it allowed us to move analytically and imaginatively across different contexts and think each case study with and through rather than against the others.¹⁰⁾ This mapping method followed an iterative process: we mapped the preliminary results of field research, identifying, locating, and describing spatial transformations in each case study, and we worked in parallel on these emerging maps in regular comparative team workshops, mediating between the specific cases. We also organized mapping sessions with local experts to then continue with more detailed field inquiry. The local experts we invited for these mapping sessions shared their knowledge about spatial transformations in a particular case study area; we documented the data by drawing directly on the emerging maps during the sessions. The experts included geographers, social anthropologists, urban planners, architects, and activists. The goal of this method was to gradually refine the resulting multi-layered analysis to the point that we could comprehensively map urban configurations. [22]

How did we use this mapping method comparatively? In our team workshops, we discussed each case study extensively, referring directly to the map. At times, the maps themselves helped us to reveal the scale of urbanization processes that otherwise would have been difficult to grasp, as the example of bypass urbanism showed (SAWYER et al., 2021). These were not existing maps of each city, but maps that we drafted to highlight key characteristics of each case study; several rounds of workshops then resulted in maps that showed areas where certain urbanization processes were dominant—what we called urban configurations (see Figure 2). Building on well-established methods of critical mapping, we designed and developed this specific method of exploratory qualitative mapping to identify these different urban configurations wherever there were insufficient quantitative data. Given that we were, to a large extent, relying on qualitative data, the field research method discussed in the previous section as well as the mapping sessions with local experts were crucial to obtaining relevant data for the map.

Figure 2: Preliminary versions of the maps of Tokyo (top left), Paris (bottom left), and Mexico City (right) displaying urban configurations in different colors. At this stage, the empirical research in each case study was completed, but the research team continued using the maps for data analysis within and across the cases.¹¹⁾ Click here to download the PDF file. [23]

Originally developed for a research project on urban development of Havana, the method is based on several mapping sessions with focus groups of architects and urban planners (PEÑA DÍAZ & SCHMID, 2007). We advanced this method in the comparative project by using the maps resulting from similar sessions in each of the eight urban territories as guidelines to conduct further interviews, share our emerging analyses and interpretations with other experts, and request their feedback. However, like the other methods presented in this article, mapping proved to be a mixed experience in practice and was not always helpful to all team members and their interlocutors for comparative analysis and theorizing. Whereas at times it generated a lively debate, on other occasions, the map was only briefly looked at before being put aside for a more traditional form of expert interviewing. This echoes numerous studies on the possibilities and limits of mapping that showed that the process of mapmaking is not neutral (e.g., CRAMPTON, 2010; MICHEL, 2010). This is true for established georeferenced cartography as well as for qualitative mapping (SLETTO, 2009). Maps are powerful instruments, and mapping has a long-standing and highly problematic legacy as a colonial method that is at odds with the postcolonial and decolonial methodological critiques which our project was built on (e.g., SMITH, 1999; TUCK & YANG, 2012). Maps also directed our gaze to certain questions and brought selected phenomena to light, while others remained hidden. They always contained a selection and hierarchization of certain data sets and narratives. However, reflecting on these inherent properties of maps also opened up possibilities for developing alternative representations of urbanization processes, as also numerous counter-mapping projects vividly demonstrated (e.g., DAMMANN & MICHEL, 2022; KOLLEKTIV ORANGOTANGO+, 2018). [24]

For our mapping method, we adopted the same principle of using systematic, yet flexible guidelines for collecting and analyzing the qualitative data used in field research. Here, the expertise of the geographers and architects in the team was crucial, as they pushed for a level of abstraction in the maps by using a metropolitan scale that would have been difficult to achieve from an anthropological perspective that is concerned primarily with the detailed analysis of the everyday. In a first step, the exploratory mapping sessions allowed the research team to discuss and visually represent various areas of the urban territory in terms of their specific socioeconomic and morphological characteristics and functions, their ongoing spatial transformations, and inhabitants' lived experiences. Thus, the map on the table around which those discussions took place was at the same time a concrete support for the discussions but also an instrument that enabled the synthesis of complex relationships. The mapping session consisted of a basic map of the urban territory (preferably a topographical map for the sake of legibility, but also an aerial view), tracing paper, colored pens, and a sound recorder. It usually started with open-ended questions which were intentionally open to interpretation and that prompted further discussion (SCHMID et al. 2018, pp.32-33). A second step was to find a way to cope with the difficult question of representation within the colonial tradition of cartography. In the example of my research on Mexico City, I again invited local scholars to discuss the preliminary results of the previous mapping sessions and to comment on the emerging maps (STREULE, 2020, p.430). Through this constant feedback loop, I established a sort of dialogical re-reading of the increasingly multi-layered map and gradually refined the cartographic representation of Mexico City's urban configurations (see also STREULE & WILDNER, 2022). In this way, the iterative nature of the research process led the team not only to embrace multi-sited strategies but also to employ multi-scalar perspectives linking local and metropolitan scales (see also HOERNING, 2021). [25]

In sum, the collaborative drafting of these emerging maps together with local experts was a crucial step in the production of knowledge; more precisely, it can be understood as a way of gradually refining the analysis of urban territories during the course of research and identifying places within each case study where data were still insufficient. Also, the research team complemented the maps with mixed data from a variety of sources, including field research findings, original archival sources, and census data, where available. We then synthesized these multiple layers of information through triangulation to produce a map that showed urban configurations where certain urbanization processes were dominant at the time. This was not to simply confirm the results by using other data or to use other methods to study the same phenomenon, but, as FLICK (2019, p.121) argued, to make the research and results more credible and fruitful. Thus, this mapping method shaped our conceptualization of data collection and further informed the emerging analysis, enabling a move from the initial data collection to a more focused one. In this way, the two-step mapping procedure helped the researchers not only to identify key characteristics of the urban territory, but also to reflect critically on knowledge production itself. [26]

3.3 Advancing regressive-progressive methods for a comparative historical analysis

After the first phase of this empirical research and initial data collection, which supported a geographical analysis and mapping of the patterns of urbanization, we employed a focused historical perspective. Our aim in using historical analysis was to understand the spatial transformations of each case since the mid-19th century based mainly on a literature review and, to a lesser extent, on original archival sources. To do this, we started with the analysis of the present situation as outlined above and then reconstructed a spatialized historical narrative of urbanization in each case, analyzing why urbanization processes emerge or vanish over time. In so doing, we identified and described significant historic moments of spatial transformation. This method allowed us to have a more differentiated and complex grasp of the present urban configurations we identified in each case. [27]

We used the well-established scholarship of urban historiography together with rich existing literature on each of our cases as the key sources for our own historical analysis. However, in this article, I focus less on describing how we worked with this secondary literature and more on how we built on these insights to advance our methodological approach. What I want to highlight is how our constant focus on urbanization processes as the centerpiece of our comparative project shaped the historical analysis and how the combination of this analysis with our field research and mapping methods resulted in a complementary set of methods that eventually enabled us to compare the spatiality of diverse urban territories across time and space. [28]

This brings me back to the main question of the project's methodological approach: How can a complex object such as the spatiality of large urban territories be studied both empirically and from a historical perspective? As suggested by comparative urban historiographers (ABU-LUGHOD, 1999; see also DAVIS, 1990; SOJA, 1989; TENORIO-TRILLO, 2012; among many others), the built environment, or surface, is one possible starting point for reconstructing a spatialized historical narrative of urbanization. We thus applied the regressive-progressive method introduced by LEFEBVRE (1991 [1974], pp.65-67), starting with the present analysis and descending into the past to identify defining moments within a specific territory, before ascending again by reconstructing the trajectory of that urban territory (SCHMID, 2023, p.36). A suitable starting point for this study was the previously elaborated map of urban configurations. The map, which was itself a synthesis of the empirical research preceding it, functioned as a basis for developing a specific spatialized historical narrative. For the historical analysis we thus built on the previous empirical analysis and assumed that we had already reached an initial understanding of the context. The outlined urban configurations then became the first point of reference for the historical research. As FREHSE (2001, p.172) noted, the potential of this regressive-progressive procedure lies in the systematization of an extremely heterogeneous corpus of historical sources—namely, the metropolitan territories themselves. Hence, with this regressive-progressive method, urban processes can be grasped as a dynamic multi-temporal process—adding a complementary perspective to the multi-sited and multi-scalar approaches provided by the field research and mapping. [29]

To reflect on this approach, we needed to understand the material, social, and political contexts from which the ideas of spatiality and historicity are derived. My study of Mexico City again serves as a helpful example. I explored Mexico City as a socially produced, multi-temporal urban territory rather than a mere geographical phenomenon. For this focused data collection and historical analysis, I relied on the extensive scholarship on urban questions in and from Mexico City to identify and describe crucial historic moments of Mexico City's spatial transformation. To sustain the analysis, this was supported by a further consultation of selected original archival sources such as historical maps and photos. Although the spatialized historical narrative I constructed by this regressive-progressive approach was oriented towards dominant processes and phases and I thereby reproduced certain dominant structures, it allowed me to underline the multi-faceted becoming of urban territories. While the result was inevitably only a partial reconstruction of a rich, spatialized history, I sought to contribute to the understanding of Mexico City's history by placing the social production of a metropolitan territory at the center of the analysis. In so doing, I achieved insights into how urbanization processes inscribe themselves into the terrain and showed that different and, at times, relatively stable social arrangements dominated the urbanization of Mexico City. I used the term urbanization regime to describe such arrangements and showed that they are distinguished from each other by specific social relations or by a certain territorial regulation. Based on the assumption that different urbanization processes are active at the same time, I conceptualized and discussed the main urbanization regimes that are fundamental to understanding Mexico City's urbanization processes today (STREULE, 2018). For the overall project, the team members used the historical analysis of each case study to clarify the temporality of urbanization processes and to differentiate the current processes of metropolitan territories. Writing up the findings of the historical analyses and reading them thorough the synthesis map not only enabled us to work on detailed and wide-ranging accounts of each urban territory, but it also provided the basis for a detailed description of the predominant urbanization processes transforming these territories (SCHMID et al. 2018, p.33). [30]

From a general point of view, of course, methods of ethnography, mapping, and historical analysis are well-established in urban studies and other spatial disciplines. Precisely because these methods are so well-known, I do not introduce them here in detail but instead focus on what building on these methods and adapting them to our specific research meant in practice; in particular, I foreground the potential of creative qualitative methods for comparative research as well as the concrete difficulties with which we as an interdisciplinary team were confronted. A critical reflection on this methodological approach also should address the variegated forms in which the research team applied the methods. As I showed, methods were practiced differently by the team members even as we worked within a shared methodological framework. Thus, the originality of the methodological procedure presented in this article was not the selection of these existing methods, but rather of how we adopted, combined, and advanced them in our attempt to grasp urbanization processes. In this sense, the inventiveness of the methods presented here extends even further insofar as they enabled us to grasp urbanization processes as a dynamic multi-sited, multi-scalar, and multi-temporal process. [31]

The comparative method applied in the project entailed a constant collaborative engagement with all case studies, with all researchers contributing their expertise and growing knowledge of one specific case. Crucially, we did not simply contrast the other cases with our own research. Rather, we learned from each other and read our own cases through the other case studies. After critically reflecting on the research process and the potential and obstacles of the complementary set of ethnographic, cartographic, and historiographical methods we used, I now discuss the main conceptual outcomes and reflect on the analytical and conceptually generative potential of our comparative analysis. The regular team workshops bringing together team members based in Singapore and Switzerland were crucial for this exchange and mutual learning in the initial phase of the research. Furthermore, these workshops were where the first contours of new concepts emerged, and they became the key for creating comparative moments. To consolidate and define these concepts, the final phase of the project was dedicated to a vital collective writing process (see Figure 1). Finalizing these articles with up to eight coauthors was probably one of the most demanding tasks of the project, as the following brief reflection also shows. [32]

4.1 First comparative moment: Identifying different urbanization processes for each case study

After several rounds of iterative inquiry, all researchers eventually produced a synthesis map for their case study: the qualitative data and the narrative elements drawn from observational fieldwork, the exploratory mapping sessions, and the historical analysis were synthesized and represented in a final map, allowing a highly interrelated and simultaneous analysis of these mixed data (for a preliminary version of such synthesis maps, see Figure 2). Each of the resulting eight synthesis maps displayed different urban configurations, indicated in different colors. This procedure corresponds to the first comparative moment of the project which was to identify and describe urbanization processes for each case study. To achieve this goal, different areas within the same urban territory had to be related, compared, and mapped as distinct urban configurations. In this process, the researcher specified the resulting urban configurations, identified their characteristics, and prepared short descriptions of each of them. Important to note here are the different languages that entered both data collection and analysis, including Turkish, Japanese, Cantonese, Mandarin, French, Mexican Spanish, English, and various Indigenous languages spoken in the areas of the case studies. [33]

We did not aim to align or harmonize the resulting maps. Instead, they showed urban configurations that are geographically and historically situated and that ideally bore names in the local language, as they are empirically grounded and emergent both as processes and as potential concepts.¹²⁾ Whereas each map displayed a wide range of different urban configurations, some similarities among the cases emerged. For example, every synthesis map showed a configuration of metropolitan centralities. However, this is not to say that the urbanization process producing this centrality was necessarily the same in all case studies. Rather, the synthesis maps provided a focus for new discussions of the specificity of each case to differentiate among the various urbanization processes we identified in the empirical research. In this way, and as I describe in the next section, we found that bringing the cases of Tokyo, Mexico City, and Los Angeles into conversation with one another was particularly fruitful for outlining the urbanization process that marked their urban configuration of metropolitan centralities (but which did not apply in the case of Lagos or Kolkata) and that we then later conceptualized as the incorporation of urban differences (HANAKATA et al., 2022). [34]

In this way, we deployed the synthesis maps as heuristic tools, and they formed an integral part of the research process. Despite its benefits, this type of visualization had obvious limits. The presence of boundaries—no matter how gradual they were—gave the impression of abrupt transitions and homogenous territories, whereas the regions under study are often very heterogeneous and bear the legacy of multiple layers of urbanization processes (SCHMID et al. 2018, p.33). We addressed these shortcomings when writing up the results of the ethnographic and historical analysis accompanying the maps. Again, the complementary quality of our methods was crucial for this first moment of comparative theorization. Whereas the maps represented patterns of urbanization, we used text to represent the pathways of urbanization. To improve the readability of the maps, we also worked together with a team of cartographers and graphic designers who assisted us in drawing these synthesis maps. [35]

4.2 Second comparative moment: Identifying urbanization processes across case studies

Having identified the urban configurations in each of our case studies, the most challenging and rewarding step of the research began, in which the collective dimension of the research and the transductive approach again became crucial: namely, putting specific urbanization processes from the different territories in conversation with one another (ibid.). This analytical step corresponds to the second comparative moment of the research—that is, identifying urbanization processes across the case studies. This second comparative moment enabled us to conceptualize new urbanization processes by drawing on our previously developed analysis and description of the urban configurations of each case study. The goal of this second step was to construct concepts that struck a delicate balance between generality and specificity so as to enable meaningful comparisons between singularities. In intense discussions during the team workshops, we were able to think together about the urban transformations we had encountered during our field research. [36]

The conceptualization of mass housing urbanization, which was based on our analysis of Hong Kong, Mexico City, and Paris, serves as a good example of our comparative procedure. Aiming both to understand the specific situation and the conditions under which each case developed, we adopted a long-term perspective to explain decisive turns and ruptures within state policies of mass housing and to understand how this urbanization process affects the entire territory. This entailed, for instance, reading the Paris case through the lens of colonial Hong Kong during the 1950s and 1960s and analyzing the global city formation and financialization in Hong Kong and Mexico City after 1980 and 1990, respectively, in view of the consequences of neoliberal restructuring in Paris during the 1970s (KOCKELKORN et al., 2023). This collective process of thinking the urban with its multiple elsewheres, as ROBINSON (2016) put it, shaped our conceptualization of mass housing urbanization as well as the analysis in each case study. Moreover, it allowed us to revisit and provincialize inherited terms and ways of understanding mass housing urbanization. This is exemplified by concepts that are relevant for understanding mass housing urbanization in Paris and in western Europe, such as "neoliberal restructuring" and the "welfare state," but that otherwise do not apply to Hong Kong and Mexico City. Therefore, our comparative analysis was important for developing a more adequate understanding of mass housing urbanization in a worldwide context. By decentering western Europe and its canonical narratives of housing histories, we were encouraged to reposition and rethink the role of the state within the process of mass housing urbanization. Thus, it was because of, not despite the diversity of the analyzed case studies that we were able to understand the inherent logic of this urbanization process. It is the stark contrast between Fordist, colonial, and financialized settings that helped us to identify the fundamental features and ensuing peripheralization of mass housing urbanization and work towards a definition that might be useful in other contexts (KOCKELKORN et al., 2023, p.607). [37]

Similarly, other concepts were developed in several rounds of discussion across the different case studies. Thus, multiple iterations were necessary to test the adequacy of the concepts, to readjust their conceptual frames, and to find coherent definitions to delineate the process. Through this transductive procedure of collective conceptual innovation and validation in the field, we were able to finalize some of the concepts while discarding or putting others on hold (SCHMID et al. 2018, p.34). Through a total of twelve intensive comparative workshops of one to two weeks, each involving the entire research team, we finally identified and conceptualized a total of ten new comparative urbanization processes. This truly collective process of building concepts and urban theory based on discussion, feedback sessions, and team workshops was one of the unique strengths of this project's methodology. [38]

This collective and comparative procedure resulted in a range of proposals for new concepts. The coauthored articles are examples of the collaborative method employed in this project. After engaging in an intense writing process, we published several articles introducing five of these concepts: popular urbanization (STREULE et al., 2020), plotting urbanism (KARAMAN et al., 2020), mass housing urbanization (KOCKELKORN et al., 2023), the incorporation of urban differences (HANAKATA et al., 2022), and bypass urbanism (SAWYER et al., 2021). Three additional processes were discussed during our workshops but have not emerged in publications so far: laminar urbanization, multilayered patchwork urbanization, and post-proletarian urbanization. [39]

A necessary step in the definition of these urbanization processes—and what could be framed as a third comparative moment—is putting them in the context of current scholarly debates and differentiating them from extant concepts. Doing this rigorously in the final phase of the conceptualization, our methodology was consistent with the open approach we followed since the beginning of this research project and again followed GTM insofar as we conducted our literature review after developing our independent analysis (CHARMAZ, 2014). To do this, we engaged in the collective writing process with the goal not only of relating our emerging concepts with existing ones, but also of conceptualizing more specific concepts and proposing them for further examination. More precise concepts are needed to put different urban outcomes into conversation with others in order to extend the ways in which we can understand and talk about the nature of the urban in all its multiplicity and complexity (ROBINSON, 2016, p.5). [40]

This is may best be exemplified by the concept of popular urbanization generated through our comparison of Mexico City, Lagos, and Istanbul (STREULE et al., 2020). We introduced this urbanization process, which has so far not been conceptualized, but which might be subsumed under wider conceptual umbrellas such as urban informality, incremental urbanism, or peripheral urbanization. However, as discussed in this article, we aimed to identify specific urbanization processes across different geographical and historical contexts. Instead of widening our concepts, we therefore narrowed their scope and thus their definitions. In doing so, we identified important systematic differences—namely, processes of marketization and commodification, the role of state agencies, and collective activities and experiences. Accordingly, we proposed three different urbanization processes that were dominated by clearly different aspects but that might all fit in other comparative concepts, such as peripheral urbanization (CALDEIRA, 2017). While popular urbanization is mainly based on self-organization, mobilization, and collectivity, plotting urbanism is oriented towards market mechanisms, and mass housing urbanization is initiated and determined by state actors (STREULE et al. 2020, p.666). This set of three concepts was the result of our comparative research, and thus it was strongly influenced by our selection of case studies. It is therefore an open list, and the concepts are revisable. It is also important to bear in mind that the organization and writing of each article—exceeding by far the project duration's end, including more than four researchers located in different parts of the world who were at the time working on various new projects—was, not surprisingly, very challenging. After numerous delays, many missed deadlines, and unusual lengthy review processes, I think it speaks to the merit of all team members, their patience, commitment and perseverance, to have all these articles published and thereby contributing to a decentered vocabulary of urbanization. [41]

From a more general perspective, the three comparative moments presented here were key to understanding how exactly we generated new concepts. These moments were crucial both for the analysis of each case study and for generating new concepts of urbanization processes. They intrinsically relate to each other to become productive (see Figure 1). Reflecting on these comparative moments, I outlined some brief examples of the conceptual outcomes. Unfortunately, space constraints do not allow me to present our findings in full detail. As these outcomes have largely been published elsewhere, I again opt here to foreground the methodological procedure we used to generate concepts of the urban from specificity. [42]

In this article, I demonstrated the potential of a creative comparative methodology for exploring variations on already defined concepts and generating new concepts of urbanization processes. Overall, this comparative approach was based on recent debates in urban studies, particularly within the scholarship on planetary urbanization and postcolonial urbanism where scholars strived to conceptualize the urban across various divides that are shaping our planet, such as those of the Global North and Global South. The goal of our comparative methodology was to acknowledge the diversity of urbanization and theorize its profound global interconnectedness. Making our methodological approach explicit showed one way to build theory and generate new concepts by bringing diverse urban experiences around the world into conversation with one another. [43]

I have also shown that using this methodology required inventing a series of creative methods and tools, including specific approaches to field research, exploratory mapping, and comparative team workshops. The focus on the implementation and application of the comparative procedure hence clarified how we adopted, combined, and adapted these methods to fit the situations of each case study, to analyze urbanization processes rather than cities, and to draw on empirical data to develop new concepts of the urban. Moreover, to compare and analyze these urbanization processes at a metropolitan scale required triangulating mixed data by combining multi-sited ethnographic field research with historical analyses and a cartographic synthesis, thereby moving beyond the usual set of data used in the literature. [44]

Furthermore, I introduced the transductive approach as a fundamental way to collect data and simultaneously conduct analysis in an iterative research process. In this way, with the methodology presented in this article I emphasized theory construction rather than the description or application of existing concepts. Put differently, this procedure—which was found to be especially productive at three moments during the comparative team workshops and the collective writing process—involved making comparisons during each stage of the analysis to advance theory development. Mapping was a key method of this procedure, as it allowed us to move analytically and imaginatively within and across different contexts, firstly by locating and describing spatial transformation and secondly by identifying and mapping urban configurations, leading finally to the generation of new concepts. These maps served as crucial heuristic devices that helped us to challenge the arbitrary division between theory and empirical research. [45]

The creative methodology and methods explained in this article enabled us to identify the patterns and pathways of urbanization in large and heterogeneous urban territories and develop new comparative concepts; but what does this qualitative, transdisciplinary and collaborative approach contribute to urban studies more broadly? A main concern of scholars in recent urban theory debates are questions of generalization, abstraction, and critical stances towards universalism (e.g., ASHER, 2019; JAZEEL, 2019; see also ANGELO & GOH, 2021; DERICKSON, 2015; GOONEWARDENA, 2018; RUDDICK, PEAKE, TANYILDIZ & DARREN, 2018; WILSON & JONAS, 2018). However, rather than offering yet another theoretical argument, I instead aimed to contribute a methodological perspective to this ongoing discussion. As I have shown throughout this article, the presented methodology relates to current debates on comparative research in the social sciences, particularly in sociology and social anthropology, and illustrates a way of thinking with and through elsewhere and keeping a balance between abstract theorizing and concrete research. [46]

Obviously, generating new concepts with a wide reach involved a moment of generalization and of moving beyond singularities (for a broader discussion, see for instance METCALFE, 2005). Yet, our goal was not to universalize concepts. Instead, we aimed to detect common underlying mechanisms, logics, regularities, and traits in the way urbanization unfolds and proceeds, thus producing similar outcomes in some of the case studies. Conceptualizing urbanization processes through this creative comparative methodology, it was possible to identify a common problematic across different times and places while taking account of the various differences between them. Thus, this methodological approach needed to not only discern the general tendencies of urbanization but also to address the specificities developing in each urban territory we studied (SCHMID, 2015). The new concepts resulting from this procedure are not comprehensive; instead, they exemplify the complexity and multiplicity of urbanization processes and help to both generalize and differentiate between the diverse urbanization processes that emerged from the case studies. Methodologically, this implied the use of a transductive strategy which maintained a dialectical relationship between theory and empirical research. Also—and I cannot emphasize this enough—this comparison and its resulting concepts are by necessity incomplete and partial and form only one of many other possible starting points for developing an enriched and revisable vocabulary of urbanization. [47]

In order to advance a postcolonial agenda by decentering urban theory, it is thus crucial, I argue, to consider the specificity of urban territories and to analyze concrete urbanization processes and manifestations of the urban on the ground. The theoretically informed empirical and situated approach to comparative urbanism I described here was particularly useful for emphasizing that urbanization processes do not simply unfold within fixed or stable urban "containers," but actively produce, unsettle, and rework urban territories and thus constantly engender new urban configurations. In light of this, spatial units of comparative analysis also had to be reconsidered. The essential task, therefore, was less to identify "new" urban forms than to investigate the historically situated and geographically specific dynamics of urbanization processes. This again shows that it is necessary to diversify sources in urban theory and to enrich the established theoretical canon with a wider palette of terms that more adequately represent the manifold emerging urban situations and urbanization processes across the globe. The goal was not to develop a unifying language, but to work collaboratively on an extended vocabulary that enables a differentiated view of the world and help to understand the dynamics of urbanization and to facilitate intellectual exchange within the field of urban studies, a field that is increasingly multilingual and multiple situated. What is clear, overall, is that theory changes practice and practice changes theory. [48]

This article resulted from the collaborative research project "Patterns and Pathways of Planetary Urbanization," carried out at the Future Cities Laboratory, Singapore-ETH Centre (FCL) and the Chair of Sociology, Department of Architecture at ETH Zurich. I especially thank colleagues on the team for generously sharing their research insights, analysis, and experiences over all these years. They are Naomi C. HANAKATA, Pascal KALLENBERGER, Ozan KARAMAN, Anne KOCKELKORN, Lindsay SAWYER, Christian SCHMID, and Tammy Kit Ping WONG. I also wish to thank my friends and colleagues Kathrin WILDNER, Angela STIENEN, Philippe REKACEWICZ, Jennifer ROBINSON, and AbdouMaliq SIMONE for their constructive advice, comments, and critiques during various phases of the research process. Thanks also to Özlem CELIK, Claudia FONSECA ALFARO, Defne KADIOĞLU and Lorena MALGAÇO, the organizers of the workshop "Dislocating Urban Studies" in 2021, for inviting me to present preliminary versions of the methodological and conceptual reflections introduced here and to all the participants for the inspiring debates. I would also like to thank two anonymous reviewers and the editor Katja MRUCK who provided very encouraging and helpful feedback on a later version of the paper. All errors and omissions remain my responsibility.

This research was supported by the Future Cities Laboratory and the Department of Architecture, ETH Zurich. The writing up of this article has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 101024446.

1) Urban researchers could, for instance, emulate current trends in social anthropology by employing creative ethnographic techniques that are essential in detailed studies of complex social phenomena such as urbanization (BALLESTERO & WINTHEREIK, 2021; SÁNCHEZ CRIADO & ESTALELLA, 2023). <back>

2) In a similar way, NIEWÖHNER and SCHEFFER (2010) used thick ethnography to produce comparability. Hence, they argued, "comparability is the result of the ethnographic inquiry, not its natural starting point" (2010, p.1). <back>

3) The transductive approach was initially proposed by LEFEBVRE (1996 [1968]), but not fully conceptualized by him. The approach is therefore not a developed method, let alone a methodology, and is congruent with the well-established abductive approach of the later GTM in many respects. However, it differs from a classical abductive procedure, as we were not going into the field with a hypothesis, to test and rework it. At the initial stage of field work, the transductive approach was perhaps closer to induction. But also not, because although conceptualized as open, it was also theoretically informed by our understanding of urbanization in general. There are subtle differences between these approaches, but in my opinion enough to make use of and engage in a further discussion on a transductive approach. Ultimately, it should not be confused with transductive logic as used by PIAGET (1986 [1932]) to refer to children's reasoning from a specific case to another specific case. <back>

4) For similar approaches beyond the field of urban studies, see "thickening comparison" (NIEWÖHNER & SCHEFFER, 2010) and "practising comparison" (DEVILLE et al., 2016). <back>

5) When using the lens of planetary urbanization—one of the guiding concepts of our project and introduced above—we understood that urbanization generates both the concentration of people, infrastructure, and information that leads to concentrated urbanization, and also an expansion of the urban fabric, resulting in extended urbanization––namely, the expansion of a dense urban territory into agricultural and sparsely populated areas (BRENNER & SCHMID, 2011, 2015; SCHMID, 2018). <back>

7) The recorrido explorativo is a form of a "floating observation," inspired by PÉTONNET's (1982) ethnographic study of a Parisian cemetery and her call for an open-minded attitude during perceptual walks, based on "the greatest possible openness and constant availability of the researcher" (p.39). Through this almost seismographic attention, different urbanization processes can be recognized (for a further critical discussion, see STREULE, 2023). <back>

8) Entrevistas en movimiento are conceived as a mobilization of the usually (mostly) site-bound and static interview situation. The considerable increase in the spatial quality of the ethnographic data results primarily from the combination of speaking and walking but also includes non-verbal statements while walking, therefore providing data that would not be collected in a classical interview situation. Importantly, I do not determine the routes of entrevistas en movimiento in advance; they rather emerge—or are improvised—during the interviews. Thematically framed by the guided narrative interview, the route articulates itself through improvisation by the interviewees and my presence. In this respect, the interview technique of entrevistas en movimiento clearly differs from the go-along method developed by KUSENBACH (2003, p.463), who explicitly applies a "natural go-along" by following the accompanied persons as they go about their daily business (STREULE, 2023, p.139). <back>

9) In the last two decades, scholars have extensively discussed such multi-sited and multi-scalar approaches in ethnography in FQS, rendering the method more attuned to a globalizing world (e.g., LAUSER, 2005; NADAI & MAEDER, 2009; NAESS, 2016). <back>

10) Feminist science and technology studies scholars and social anthropologists referred to this as "a diffractive methodology" (MURRIS & BOZALEK, 2019, p.1504), an alternative method to reflection and reflexivity that enables scholars to engage affirmatively with difference by reading texts (rather than maps) through and not against one another (e.g., BARAD, 2011, 2014; HARAWAY, 1997; MURRIS & BOZALEK, 2019). Thanks to the anonymous reviewer for pointing this out. <back>

11) In order to improve the readability of the maps, we worked together with the cartographer Philippe REKACEWICZ. The authors of the maps in Figure 2 are Naomi HANAKATA for the Tokyo map, Anne KOCKELKORN for the Paris map, and Monika STREULE for the Mexico City map. <back>

12) For an extended discussion on the importance of language in doing qualitative research and persisting inequalities in academic discourse, see CISNEROS PUEBLA et al. (2006). <back>

Abu-Lughod Janet L. (1999). New York, Chicago, Los Angeles. America's global cities. Minneapolis, MN: University of Minnesota Press.

Amit, Vered (Ed.) (2000). Constructing the field: Ethnographic fieldwork in the contemporary world. London: Routledge.

Angelo, Hillary & Goh, Kian (2021). Out in space: Difference and abstraction in planetary urbanization. International Journal of Urban and Regional Research, 45(4), 732-744.

Angelo, Hillary & Wachsmuth, David (2015). Urbanizing urban political ecology. A critique of methodological cityism. International Journal of Urban and Regional Research, 39(1), 16-27.

Asher, Kiran (2019). When we cannot not compare. A commentary on Tariq Jazeel's "singularity". A manifesto for incomparable geographies. Singapore Journal of Tropical Geography, 40(1), 26-29.

Ballestero, Andrea & Winthereik, Brit Ross (Eds.) (2021). Experimenting with ethnography. Durham: Duke University Press.

Barad, Karen (2011). Nature’s Queer performativity. Qui Parle, 19(2), 121-158.

Barad, Karen (2014). Diffracting diffraction: Cutting together-apart. Parallax, 20(3), 168-187.

Baur, Nina; Mennel Stephen & Million, Angela (2021). The refiguration of spaces and methodological challenges of cross-cultural comparison. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 22(2), Art. 25, http://dx.doi.org/10.17169/fqs-22.2.3755 [Accessed: January 27, 2023].

Baur, Nina; Castillo Ulloa, Ignacio; Mennell, Stephen & Million, Angela (2021). The refiguration of spaces and the refiguration of epistemic cultures: The changing balance of involvement and engagement in fundamental and applied research. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 22(3), Art. 21, http://dx.doi.org/10.17169/fqs-22.3.3810 [Accessed: January 27, 2023].

Brenner, Neil & Schmid, Christian (2011). Planetary urbanization. In Matthew Gandy (Ed.), Urban constellations (pp.10-13). Berlin: Jovis.

Brenner, Neil & Schmid, Christian (2015). Towards a new epistemology of the urban?. City, 19(2-3), 151-182.

Brill, Frances (2021). Practising comparative urbanism: Methods and consequences. Area, 54(2), 252-259.

Brill, Frances (2022). Constructing comparisons: Reflecting on the experimental nature of new comparative tactics. Urban Studies, 59(8), 1754-1759.

Bryant, Antony (2009). Grounded theory and pragmatism: The curious case of Anselm Strauss. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 10(3), Art. 2, https://doi.org/10.17169/fqs-10.3.1358 [Accessed: August 1, 2023].

Caldeira, Teresa (2017). Peripheral urbanization: Autoconstruction, transversal logics, and politics in cities of the global south. Environment and Planning D: Society and Space, 35(1), 3-20, https://doi.org/10.1177/0263775816658479 [Accessed: January 27, 2023].

Candea, Matei (2018). Comparison in anthropology. The impossible method. Cambridge: Cambridge University Press.

Charmaz, Kathy (2014). Constructing grounded theory. A practical guide through qualitative analysis. London: Sage.

Cisneros Puebla, César A.; Domínguez Figaredo, Daniel; Faux, Robert; Kölbl, Carlos & Packer, Martin (2006). About qualitative research epistemologies and peripheries. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 7(4), Art. 4, https://doi.org/10.17169/fqs-7.4.158 [Accessed: January 27, 2023].

Coleman, Rebecca (2017). A sensory sociology of the future: Affect, hope and inventive methodologies. The Sociological Review, 65(3), 525-543.

Crampton, Jeremy W. (2010). Mapping. A critical introduction to cartography and GIS. Malden, MA: Wiley-Blackwell.

Dammann, Finn & Michel, Boris (Eds.) (2022). Handbuch. Kritisches Kartieren. Bielefeld: transcript.

Davis, Mike (1990). City of quartz. Excavating the future in Los Angeles. London: Verso.

Delgado, Manuel (2007). Sociedades movedizas. Pasos hacia una antropología de las calles [Shifting societies. Steps towards an anthropology of the streets]. Barcelona: Editorial Anagrama.

Derickson, Kate D. (2015). Urban geography I: Locating urban theory in the "urban age". Progress in Human Geography, 39(5), 647-657.

Deville, Joe; Guggenheim, Michael & Hrdličková, Zuzanna (Eds.) (2016). Practising comparison: Logics, relations, collaborations. Manchester: Mattering Press.

Färber, Alexa (2021). The anthropology of urban comparison: Urban comparative concepts and practices, the entrepreneurial ethnographic self and their spatializing dimensions. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 22(3), Art. 13, http://dx.doi.org/10.17169/fqs-22.3.3782 [Accessed: January 27, 2023].

Falzon, Mark-Anthony (Ed.) (2009). Multi-sited ethnography. Theory, praxis and locality in contemporary research. London: Ashgate.

Fox, Richard G. & Gingrich, Andre (Eds.) (2002). Anthropology, by comparison. London: Routledge.

Frehse, Fraya (2001). Potencialidades do método regressivo-progressivo. Pensar a cidade, pensar a história [Potentialities of the regressive-progressive method. Think the city, think the history]. Tempo Social, 13(2), 169-184.

García Canclini, Nestor (1996). Los viajes metropolitanos [Metropolitan travel]. In Nestor García Canclini, Alejandro Castellanos & Ana Rosas Mantecón (Eds.), La ciudad de los viajeros [The city of travelers] (pp.11-41). México DF: Editorial Grijalbo.

Goonewardena, Kanishka (2018). Planetary urbanization and totality. Environment and Planning D: Society and Space, 36(3), 456-473.

Gough, Katherine V. (2012). Reflections on conducting urban comparison. Urban Geography, 33(6), 866-878.

Hanakata, Naomi C. (2020). Tokyo—an urban portrait: Looking at a megacity through its differences. Berlin: Jovis.

Hanakata, Naomi C.; Streule, Monika & Schmid, Christian (2022). Incorporation of urban differences in Tokyo, Mexico City, and Los Angeles. City, 26(5-6), 791-819, https://www.doi.org/10.1080/13604813.2022.2126231 [Accessed: January 27, 2023].

Haraway, Donna (1997). Modest_witness@second_millenium: FemaleMan_meets_OncoMouse: Feminism and technoscience. New York, NY: Routledge.

Hoerning, Johanna (2021). Comparing actors and scales. Methodological perspectives from a political sociology of the refiguration of spaces. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 22(3), Art. 1, http://dx.doi.org/10.17169/fqs-22.3.3763 [Accessed: January 27, 2023].

Ingold, Tim & Vergunst, Jo Lee (Eds.) (2008). Ways of walking. Ethnography and practice on foot. Aldershot: Ashgate.

Jazeel, Tariq (2019). Singularity. A manifesto for incomparable geographies. Singapore Journal of Tropical Geography, 40(1), 5-21.

Karaman, Ozan; Sawyer, Lindsay; Schmid, Christian & Wong, Kit Ping (2020). Plot by plot: Plotting urbanism as an ordinary process of urbanisation. Antipode, 52(4), 1122-1151.

Kockelkorn, Anne (2017). The Social Condenser II: Eine Archäologie zu Wohnungsbau und Zentralität in der Pariser Banlieue am Beispiel der Wohnungsbauten von Ricardo Bofill und Taller de Arquitectura. Dissertation, Department of Architecture, ETH Zurich, Switzerland, https://www.research-collection.ethz.ch/handle/20.500.11850/245661 [Accessed: January 27, 2023].

Kockelkorn, Anne; Schmid, Christian; Streule, Monika & Wong, Kit Ping (2023). Peripheralization through mass housing urbanization in Hong Kong, Paris and Mexico City. Planning Perspectives, 38(3), 603-641, https://doi.org/10.1080/02665433.2022.2126997 [Accessed: July 16, 2023].

Kusenbach, Margarethe (2003). Street phenomenology. The go-along as ethnographic research tool. Ethnography, 4(3), 455-485.

Lancione, Michele & McFarlane, Colin (2016). Life at the urban margins: Sanitation infra-making and the potential of experimental comparison. Environment and Planning A: Economy and Space, 48(12), 2402-2421.

Lauser, Andrea (2005). Translokale Ethnographie. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 6(3), Art. 7, https://doi.org/10.17169/fqs-6.3.26 [Accessed: June 12, 2023].

Lee, Jo & Ingold, Tim (2006). Fieldwork on foot. Perceiving, routing, socializing. In Simon Coleman & Peter Collins (Eds.), Locating the field (pp.67-85). Oxford: Berg.

Lefebvre, Henri (1996 [1968]). Right to the city. In Eleonore Kofman & Elisabeth Lebas (Eds.), Writings on cities by Henri Lefebvre (pp.63-182). Oxford: Blackwell.

Leitner, Helga & Sheppard, Eric (2016). Provincializing critical urban theory: Extending the ecosystem of possibilities. International Journal of Urban and Regional Research, 40(1), 228-235.

Lury, Celia & Wakeford, Nina (Eds.) (2012). Inventive methods. The happening of the social. London: Routledge.

Metcalfe, Mike (2005). Generalisation: Learning across epistemologies. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 6(1), Art. 17, https://doi.org/10.17169/fqs-6.1.525 [Accessed: June 12, 2023].

Michel, Boris (2010). Für eine poststrukturalistische Perspektive auf das Machen und die Macht von Karten. Replik auf Ball und Petsimeris. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 11(3), Art. 28, https://doi.org/10.17169/fqs-11.3.1549 [Accessed: January 27, 2023].

Murris, Karin & Bozalek, Vivienne (2019). Diffracting diffractive readings of texts as methodology: Some propositions. Educational Philosophy and Theory, 51(14), 1504-1517.

Myers, Garth (2014). From expected to unexpected comparisons: Changing the flows of ideas about cities in a postcolonial urban world. Singapore Journal of Tropical Geography, 35(1), 104-118.

Nadai, Eva & Maeder, Christoph (2009). Fuzzy fields. Multi-sited ethnography in sociological research. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 6(3), Art. 28, https://doi.org/10.17169/fqs-6.3.22 [Accessed: January 27, 2023].

Naess, Hans Erik (2016). Creating "the field": Glocality, relationality and transformativity. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 17(3), Art. 15, https://doi.org/10.17169/fqs-17.3.2600 [Accessed: June 12, 2023].

Niewöhner, Jörg & Scheffer, Thomas (2010). Introduction. Thickening comparison: On the multiple facets of comparability. In Thomas Scheffer & Jörg Niewöhner (Eds.), Thick comparison. Reviving the ethnographic aspiration (pp.1-15). Leiden: Brill.

Peña Díaz, Jorge & Schmid, Christian (2007). Mapeando La Habana [Mapping Havana]. Planificación física Cuba, 12, 46-52.

Pétonnet, Colette (1982). L'Observation flottante. L'exemple d'un cimetière parisien [Floating observation. The example of a Parisian cemetery]. L'Homme, 22(4), 37-47.

Ren, Julie & Luger, Jason (2015). Comparative urbanism and the "Asian city": Implications for research and theory. International Journal of Urban and Regional Research, 39(1), 145-156.

Reichertz, Jo (2010). Abduction: The logic of discovery of grounded theory. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 11(1), Art. 13, https://doi.org/10.17169/fqs-11.1.1412 [Accessed: August 1, 2023].

Robinson, Jennifer (2006). Ordinary cities. Between modernity and development. London: Routledge.

Robinson, Jennifer (2011). Cities in a world of cities: The comparative gesture. International Journal of Urban and Regional Research, 35(1), 1-23.

Robinson, Jennifer (2016). Thinking cities through elsewhere. Comparative tactics for a more global urban studies. Progress in Human Geography, 40(1), 3-29.

Robinson, Jennifer (2022a). Introduction: Generating concepts of "the urban" through comparative practice. Urban Studies, 59(8), 1521-1535.

Robinson, Jennifer (2022b). Comparative urbanism: Tactics for global urban studies. Newark, NJ: Wiley.

Ruddick, Sue; Peake, Linda; Tanyildiz, Gökbürü S. & Darren, Patrick (2018). Planetary urbanization: An urban theory for our time?. Environment and Planning D: Society and Space, 36(3), 387-404.

Sánchez Criado, Tomás & Estalella, Adolfo (2023). An ethnographic inventory: Field devices for anthropological inquiry. London: Routledge.

Sawyer, Lindsay; Schmid, Christian; Streule, Monika & Kallenberger, Pascal (2021). Bypass urbanism: Re-ordering center-periphery relations in Kolkata, Lagos and Mexico City. Environment and Planning A: Economy and Space, 53(4), 675-703, https://doi.org/10.1177/0308518X20983818 [Accessed: January 27, 2023].

Schmid, Christian (2015). Specificity and urbanization. A theoretical outlook. In Roger Diener, Roger, Jacque Herzog, Marcel Meili, Pierre de Meuron, Manuel Herz, Christian Schmid & Milica Topalovic (Eds.), The inevitable specificity of cities (pp.282-297). Zurich: Lars Müller Verlag.

Schmid, Christian (2018). Journeys through planetary urbanization: Decentering perspectives on the urban. Environment and Planning D: Society and Space, 36(3), 591-610.

Schmid, Christian (2023) Theory building through comparative strategies. In Christian Schmid & Monika Streule (Eds.), Vocabularies for an urbanising planet. Theory building through comparison (pp.29-38). Basel: Birkhäuser.

Schmid, Christian & Streule, Monika (Eds.) (2023a). Vocabularies for an urbanising planet. Theory building through comparison. Basel: Birkhäuser.

Schmid, Christian & Streule, Monika (2023b). Paradigms of urbanisation. The comparative outlook. In Christian Schmid & Monika Streule (Eds.), Vocabularies for an urbanising planet. Theory building through comparison (pp.361-372). Basel: Birkhäuser.

Schmid, Christian; Karaman, Ozan; Hanakata, Naomi C; Kallenberger, Pascal; Kockelkorn, Anne; Sawyer, Lindsay; Streule, Monika & Wong, Kit Ping (2018). Towards a new vocabulary of urbanisation: A comparative approach. Urban Studies, 55(1), 19-52.

Schwarz, Anke & Streule, Monika (2016). A transposition of territory. Decolonial perspectives in current urban research. International Journal of Urban and Regional Research, 40(5), 1000-1016.

Schwarz, Anke & Streule, Monika (2022). Rendering territory (in)visible. Approaching urban struggles through a socio-territorial lens. In Andrea Mubi Brighenti & Mattias Kärrholm (Eds.), Territories, environments, politics (pp.136-152). London: Routledge.

Sletto, Bjørn I. (2009). "We drew what we imagined". Participatory mapping, performance, and the arts of landscape making. Current Anthropology, 50(4), 443-476.

Smith, Linda Tuhiwai (1999). Decolonizing methodologies: Research and Indigenous peoples. London: Zed Books.

Söderström, Ola (2013). Cities in relations. Trajectories of urban development in Hanoi and Ouagadougou. Oxford: Wiley-Blackwell.

Soja, Edward W. (1989). Postmodern geographies. The reassertion of space in critical social theory. London: Verso.

Streule, Monika (2013). The trend towards transdisciplinarity: A critical evaluation of an ambivalent practice in qualitative urban studies. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 15(1), Art. 17, https://doi.org/10.17169/fqs-15.1.1995 [Accessed: January 27, 2023].

Streule, Monika (2016). Ethnography of urban territories: A transdisciplinary analysis of metropolitan urbanization processes in Mexico City. Dissertation, Department of Architecture, ETH Zurich, Switzerland, https://www.research-collection.ethz.ch/handle/20.500.11850/118788 [Accessed: January 27, 2023].

Streule, Monika (2017). Post- und dekoloniale Perspektiven der Stadtforschung. In Rebecca Steger, Marie Ludwig, Julia Brychcy, Elisabeth Pütz & Kyra Sell (Eds.), subalternativen (pp.79-104). Münster: edition assemblage.

Streule, Monika (2018). Ethnografie urbaner Territorien. Metropolitane Urbanisierungsprozesse von Mexiko-Stadt. Münster: Westfälisches Dampfboot.

Streule, Monika (2020). Doing mobile ethnography. Grounded, situated and comparative. Urban Studies, 57(2), 421-438.

Streule, Monika (2023). How to set ethnography in motion?. In Tomás Sánchez Criado & Adolfo Estalella (Eds.), An ethnographic inventory. Field devices for anthropological inquiry (pp.133-142). London: Routledge.

Streule, Monika & Wildner, Kathrin (2022). Gemeinsam Karten lesen – kollektive Wissensproduktion in der Stadtforschung. In Finn Dammann & Boris Michel (Eds.), Handbuch. Kritisches Kartieren (pp.125-137). Bielefeld: transcript.

Streule, Monika; Karaman, Ozan; Sawyer, Lindsay & Schmid Christian (2020). Popular urbanization. Conceptualizing urbanization processes beyond informality. International Journal of Urban and Regional Research, 44(4), 652-672.

Tenorio-Trillo, Mauricio (2012). I speak of the city: Mexico City at the turn of the twentieth century. Chicago, IL: The University of Chicago Press.

Teo, Shaun S.K. (2022). Shared projects and symbiotic collaborations: Shenzhen and London in comparative conversation. Urban Studies, 59(8), 1694-1714.

Ward, Kevin (2010). Towards a relational comparative approach to the study of cities. Progress in Human Geography, 34(4), 471-487.

Wilson, David & Jonas, Andrew E.G. (2018). Planetary urbanization: New perspectives on the debate. Urban Geography, 39(10), 1576-1580.

Wood, Astrid (2020). Tracing urbanism: Methods of actually doing comparative studies in Johannesburg. Urban Geography, 41(2), 293-311.

Yengoyan, Aram A. (Eds.) (2010). Modes of comparison: Theory & practice. Ann Arbor, MI: University of Michigan Press.

Streule, Monika (2023). How to compare specificity, build concepts, and change theory: A creative methodology to grasp urbanization processes [48 paragraphs]. Forum Qualitative Sozialforschung / Forum: Qualitative Social Research, 24(3), Art. 11, https://dx.doi.org/10.17169/fqs-24.3.4016.

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