New perspectives, ruptures and challenges in the cities of the 21st centuryThe contemporary city is undergoing profound transformations driven by economic globalization, neoliberal urban policies, and the reconfiguration of social and cultural structures. In this scenario, socio-spatial fragmentation and residential segregation have become consolidated as structural characteristics of urban space. This is a context marked by the intensification of inequalities and the reconfiguration of ways of inhabiting and producing the city. Departing from the conventional center-periphery or inclusion-exclusion dichotomies, contemporary urbanization is characterized by multi-scale fractures, wherein unequal access to services, rights, and opportunities gives rise to territories in tension. This process of change is influenced by explicit or tacit public policies, the dynamics of a highly financialized real estate market, and institutional and social practices that perpetuate dynamics of territorial differentiation.

Residential segregation -understood as the unequal distribution of social groups in urban space based on income, origin, educational level or migratory status- is not a recent phenomenon, but it has acquired more complex forms in recent decades: from the self-segregation of elites in exclusive and exclusive enclaves or gated communities, to the residential exclusion of the lower classes -displaced to peripheral, disadvantaged areas or with limited access to urban services- where structural vulnerability persists. This is compounded by vertical segregation, intra-neighborhood differentiation and microfragmentation. Even without visible physical barriers, a city can be deeply segregated. When this is intensified and articulated with urban structures that limit connectivity, accessibility and interaction -such as large road infrastructures, fragmented planning or the absence of integrating public spaces-, and when mechanisms of territorial stigmatization also operate, a fragmentation of the urban fabric is consolidated, which transcends the physical to also affect social relations, imaginaries and the full exercise of urban rights, the right to the city.

Urban fragmentation not only implies territorial differentiation, but also the rupture of functional, social and symbolic links between urban areas, with direct effects on cohesion, equity and sustainability. As recent literature has pointed out, fragmentation should not be reduced to a morphological phenomenon: it constitutes a socio-spatial process deeply linked to the logic of capitalist production of space. It manifests itself in multiple dimensions -material, symbolic, environmental, mobility- and therefore requires a comprehensive and comparative analytical approach. From this perspective, fragmentation should not only be conceived as an effect of inequality, but also as a mechanism that contributes to its reproduction, reinforcing pre-existing power structures. Segregation operates as a device of spatial differentiation, while fragmentation is presented as its most structural, entrenched and legitimized manifestation. Both, in their articulation, produce fragmented cities, where urban rights are distributed asymmetrically and where territorial location has a decisive influence on possible social trajectories.

Recent research, and some of the contributions in this monograph, point to a sustained increase in socioeconomic segregation, with an apparent attenuation of ethnic or racial segregation in some contexts, although this interpretation requires nuances. The extension of the urban fabric, intra-urban displacements and the consolidation of patterns of forced mobility -by expulsion, eviction or relocation- have contributed to reproduce more diffuse but equally effective forms of segregation. At the same time, explanations focused exclusively on economic variables are insufficient today. Factors such as identity or the meanings and values assigned to the territory acquire an increasingly relevant role, especially at micro scales such as the neighborhood, the block or the building.

Residential preferences and choices, together with everyday spatial and temporal practices, shape the concrete forms that segregation and its fragmented expressions take. These behavioral patterns are influenced by social elements such as group membership, identities, ideologies, as well as economic, cultural and political factors. Therefore, approaching these phenomena requires an open and integrative view, capable of articulating different scales and spatiotemporal processes. The challenge lies in identifying, characterizing and measuring fragmentation and segregation from complementary approaches: social, economic, housing, environmental and cultural.

In summary, residential segregation and urban fragmentation are multidimensional processes that reflect and reproduce social inequalities. They are the result of the interaction of economic (income disparities, exclusionary real estate markets), social (preferences and prejudices, community networks), historical (planning legacy, past legal segregation) and political (state models, public investment in housing, land use regulations) factors. Understanding them critically is a fundamental step towards imagining and being able to propose fairer, more livable and cohesive cities. With this objective in mind, this monographic issue of Cities brings together research that, from diverse theoretical and empirical approaches, addresses these issues with the aim of contributing to the academic debate and to the formulation of more equitable urban policies.

From this perspective, the monographic issue of the journal Ciudades proposes to address the spatial manifestations of urban inequality. The open call for papers received a wide response -nearly forty proposals-, which required a rigorous selection process in accordance with the journal’s editorial criteria. Priority was given to those contributions that offered a systemic and multidimensional view of the processes of segregation and fragmentation. As a result, twelve articles have been included in the monographic section and five in the miscellaneous section. The selected papers provide solid methodological approaches and relevant empirical studies that enrich the understanding of these contemporary urban dynamics. The monograph brings together twelve contributions that analyze residential segregation and urban fragmentation from varied theoretical, methodological and empirical approaches, with case studies covering multiple geographical contexts that are briefly presented below.

The article by Sako Musterd (University of Amsterdam) opens the set of contributions with an excellent synthetic analysis of the theoretical perspectives and political visions that explain urban segregation. The paper examines this phenomenon from a three-pronged approach: institutional context, structural conditions and individual preferences. It raises the question of when segregation should be considered problematic and whether the effects generated justify interventions. From this perspective, the effects of segregation are analyzed, highlighting that, if the concentration of poverty exceeds certain thresholds, additional negative consequences may be generated, such as social exclusion or difficulties in economic exchanges. The text compares levels of segregation in different cities and regions, noting that ethnic segregation has decreased in some European contexts, while socioeconomic segregation has clearly increased in recent years. From a political perspective, Musterd identifies that welfare regimes play a key role in shaping segregation, with three main approaches: neoliberal, which favors individual choice and market processes; social democratic, which seeks to reduce inequality through redistributive policies and housing market regulation; and populist, which emphasizes exclusion and the targeting of vulnerable groups as responsible for urban problems. Neoliberal welfare regimes, globalized cities, unequal states and cities, and regimes that developed racial inequality have stimulated residential segregation. In contrast, social democratic welfare states, less globally connected cities and territories governed with policies that fight racism have created conditions for developing habitats in which segregation is reduced. The article concludes with a reflection on the importance of an integrated theoretical framework for understanding segregation and the challenges for effective policy making. It argues for avoiding stigmatizing approaches and for the development of strategies that promote equity, without imposing forced models that pursue artificial social mixing.

The article by Rodríguez Suárez, Viedma Guiard and Hernández Aja (Universidad Politécnica de Madrid) analyzes the relationship between income and housing quality as key factors in urban fragmentation and residential vulnerability in Spain. Based on the development of a new Housing Indicator for the 2021 Catalogue of Vulnerable Neighborhoods, the article examines how the combination of cadastral and income distribution data allows a detailed assessment of residential inequalities in the main Spanish cities: Madrid, Barcelona, Valencia and Seville. In this way, the research addresses the phenomenon at the scale of metropolitan areas and establishes that the most relevant residential segregation is configured by the socioeconomic structure and the construction characteristics of housing. It identifies that residential vulnerability in these large cities tends to be concentrated in peripheral areas and in neighborhoods with lower building quality, while higher income areas tend to have better preserved housing stock. The paper considers that, although the use of indicators allows for a detailed quantitative view of urban vulnerability, it is crucial to complement these studies with qualitative analyses to avoid simplifications and better understand socio-spatial dynamics. The importance of integrating income as a key factor in the assessment of residential vulnerability and in the design of more equitable urban policies is emphasized.

Beyond the theoretical and methodological contributions and the studies referring to Spanish cities, it is interesting to highlight the value of the contributions on different urban spaces in Latin American countries. The publication of these studies allows for a rich comparative dimension. Specifically, the monograph also includes several articles on different Brazilian, Mexican, Nicaraguan, Colombian and Chilean urban areas. These contributions contain valuable epistemological reflections that are applied in different case studies referring to the dynamics of segregation, the forms of fragmentation and the patterns of spatial distribution of the different demographic groups, as well as their housing patterns related to the characteristics and typologies of the dwellings.

In the first of these papers, Maria Encarnação Beltrão Sposito (Universidade Estadual Paulista, Brazil) examines sociospatial fragmentation in two intermediate Brazilian cities, Maringá and Ribeirão Preto, from a theoretical and empirical perspective. The concept of sociospatial fragmentation is used to analyze how the dynamics of residential, commercial and service use have reconfigured the urban structure in both cities, intertwining changes in the urban fabric, spatial practices and social imaginaries. It starts with a review of the concept of segregation, highlighting its evolution from the Chicago School to contemporary critical reinterpretations that link it to processes of self-segregation. The research, based on thematic mapping, interviews and fieldwork, reveals how urban fragmentation not only responds to patterns of socioeconomic inequality, but also manifests itself in the way different groups manage social difference in urban space. In Maringá, fragmentation is reflected in a differentiation between the north, with a lower income population and social housing programs, and the south, dominated by sectors with greater purchasing power and gated developments. Despite the importance of the traditional center, new centralities are emerging around shopping centers and exclusive enclaves. In Ribeirão Preto, fragmentation is more consolidated, with a North-South separation marked by extreme socioeconomic differences. The North concentrates low-income population and informal settlements, while the South is home to gated communities and large commercial complexes, generating a segregation that reinforces spatial and social inequalities. The most relevant contribution of the article focuses on demonstrating that socio-spatial fragmentation is not only a physical phenomenon, but is also rooted in social representations, where the stigmatization of space plays a key role in urban exclusion.

On the scale of medium-sized cities, Bellet, Lasala, Andrés and Cebrián (Universities of Lleida, Burgos and Castilla-La Mancha) start from the premise that spatial proximity between social groups does not imply less segregation, but can hide significant differences in these processes. The article analyzes how this dynamic manifests itself in 34 urban areas of medium-sized cities in the interior of the peninsula, where the different sociodemographic groups are shown to be “together but separate”. To explain this apparently mixed distribution, in addition to global structural factors, the study considers the importance of contextual and local factors in each type of city. The analysis emphasizes that socio-spatial differences are conditioned by social status, life cycle and, especially, by the housing tenure regime. Through the use of indicators such as the Gini index and principal component analysis (PCA), it is shown that high-income segregation is more intense than low-income segregation. In addition, it is highlighted that high income appears more concentrated in certain privileged enclaves and that a gradual increase in low income segregation is observed where high unemployment rates and a strong presence of immigrant population converge. Likewise, the study shows that the levels of inequality and intensity of segregation are, on the whole, lower in medium-sized cities than in large urban areas, except in some high-income cases. As in large cities, it also shows that housing tenure (ownership vs. rental) emerges as a key factor of social and spatial differentiation. The article concludes by considering that, although medium-sized cities show less inequality, there are specific segregation patterns that require urban policies adjusted to their particularities, with special attention to housing and socio-spatial mobility.

Focusing on the reality of Brazilian urban segregation, the article by Doralice Sátyro Maia, Demóstenes Andrade de Moraes and Camila Coelho Silva (Universidade Federal da Paraíba, Universidade Federal de Campina Grande and Instituto Federal de Educação, Ciência e Tecnologia do Sertão Pernambucano, Brazil) analyzes socio-spatial segregation in João Pessoa. The work reflects on the historical persistence of socio-spatial differences and their manifestation in access to housing, urban integration and the quality of life of the vulnerable population. From a critical perspective, it is argued that segregation is not only a consequence of socio-economic inequality, but also a structural mechanism of urbanization that has conditioned the occupation of space in João Pessoa. Historical patterns of segregation are identified between the “Upper City”, where the elite and institutions are concentrated, and the “Lower City”, occupied by workers and people in precarious situations. This research highlights how the most disadvantaged settlements, located in urban interstices such as river banks and risk zones, have historically been relegated by urban policies that have prioritized the valorization of the land. In addition, the expansion of the city has reinforced spatial exclusion, pushing the most vulnerable sectors into areas with scarce infrastructure and services. Despite recent urbanization and settlement regularization policies, deficits persist in urban integration, public investment and recognition of the rights of the inhabitants of these spaces. After analyzing several variables and trends, it is clear that segregation in João Pessoa is not only maintained, but continues to be a central axis in the structuring of the city.

Another look at the scale of large cities is contained in the article by Daniel Sorando (University of Zaragoza). This paper analyzes the evolution of residential segregation in Madrid between 2001 and 2021, using disaggregated census data. This research explains the importance of considering income levels and housing characteristics to understand the changes in the intensity of urban segregation over these two decades, marked by real estate cycles and transformations in the socio-labor structure of the city. The study shows that in 2011 Madrid had one of the highest levels of socioeconomic segregation in Europe, driven by the real estate bubble and its consolidation as a global city. However, in the following decade, the dynamics of professionalization led to a certain mix between the most privileged and the most precarious categories, identifying two key processes. On the one hand, he points to the growing gentrification in the urban center, with an expansion of professionals and upper classes that have displaced the traditionally resident population. On the other hand, he explains the suburbanization of poverty, with the transfer of the working classes to the peripheries, especially in municipalities in the south of Madrid. Sorando explains that inequality in the Spanish capital remains high, although with an increasingly complex configuration. While the upper categories indicate a certain reduction in segregation indicators, the middle classes have tended to isolate themselves from the precarious sectors, consolidating new socio-spatial frontiers in this urban agglomeration.

The study of the manifestations of inequality requires tools for its measurement, so it is essential to establish models to quantify the processes. The proposal by Rubiales, López, Gil and García (University of Barcelona) contains an interesting methodology for understanding, quantifying and measuring fragmentation. This article proposes an operational definition of the concept of urban fragmentation and develops a quantitative methodology for its analysis, applied to the study of the foreign-born population in the main urban areas of Spain (Madrid, Barcelona, Seville, Bilbao and Valencia). Conceptualizing fragmentation as the form, more or less clustered or dispersed, of the unequal distribution of a group in urban space, classical indicators of segregation (Segregation Index) are combined with measures of spatial autocorrelation (local Moran Index) and socioeconomic characterization (relationship with median income). Census data from 2001 and 2021 are used and the research results reveal interesting distinct patterns. On the one hand, the African population shows high segregation combined with a fragmented spatial distribution and linkage to low-income areas. In contrast, Latin American population groups show less segregation and clustering in vulnerable peripheries. The European and Asian populations show less association with low-income areas. The diachronic mapping presented in the paper also shows dynamics of displacement from urban centers to peripheries in contexts of increasing urban fragmentation. These findings allow the authors to limit the definition of fragmentation to a process other than segregation, which is relevant for understanding the new forms of spatial inequality under post-Fordist capitalism. Finally, as in other papers presented in this monograph, the need to combine quantitative and qualitative approaches for a comprehensive analysis of the phenomena of urban vulnerability is emphasized.

An interesting reflection on the Mexican case is reflected in the study by Alessandra Cireddu et al. (Tecnologico de Monterrey, Universidad de Guadalajara and other centers). This work analyzes the notion of proximity in segregated urban environments, focusing on two case studies in the Guadalajara metropolitan area. On the one hand, it analyzes the coexistence between luxury gated communities in Zona Real and the traditional neighborhood of San Juan de Ocotán and, on the other hand, it considers the transformation of the historic neighborhood of Huentitán el Alto, with the insertion of gated housing in its urban fabric. It is argued that proximity should not be understood only as a matter of physical distance, but as a social and economic experience influenced by urban conditions and daily mobility. Based on quantitative and qualitative methodologies, such as the analysis of proximity indexes and interviews on the network of places of daily life, it is shown that segregation modifies the way in which inhabitants perceive and experience proximity in their environment. The results show that, in gated communities, proximity is relative due to the predominant use of automobiles, which generates social isolation. In contrast, in traditional neighborhoods there is a greater mix of uses and a compact urban structure that favors proximity, although the low quality of public space and the lack of infrastructure also affect this experience. In addition, in small subdivisions such as Villas de Huentitán, proximity is more “emotional” than functional, since the inhabitants carry out their daily activities in other parts of the city, linked to their family and work networks. The article’s concepts of dilated, limited, emotional and ideal proximity are very interesting. Based on their differences, the paper finally argues that socio-spatial segregation redefines proximity in Latin American cities, making it necessary to rethink urban policies from a perspective that considers the lived experience of the inhabitants.

A study on large cities refers to the case of Las Palmas de Gran Canaria, focusing specifically on the analysis of the segregation of the population of foreign origin. The article by Juan Manuel Parreño Castellano and Víctor Jiménez Barrado (University of Las Palmas de Gran Canaria) uses spatial indicators and establishes a statistically significant model linking the location of this population with income and the structure of the real estate market. Interestingly, the study distinguishes between voluntary and involuntary segregation. It starts from the idea that, in general, in the Spanish context, segregation is mainly determined by income, which limits the housing options of immigrants, concentrating them in areas with lower residential quality. However, cultural and social factors that influence settlement patterns are also identified. The analysis of census data and the residential segregation index shows that the South American population has a more dispersed distribution, while Africans and Europeans show higher levels of concentration in certain neighborhoods. The correlation between income and location reveals that the European population is located in areas of higher purchasing power, while the African and Latin American groups reside in areas of lower housing quality. The article concludes that residential segregation in this city has decreased in the last decade, although significant differences persist according to origin and income. As in other papers presented, the need for urban policies that integrate the migratory perspective and reduce spatial inequality is highlighted.

The study by Alfonso Roa and Osorio Arias (Universidad Externado de Colombia) on the spatial differences between enrichment and impoverishment in Bogota. This work studies the spatial effects of residential segregation by social class on housing supply prices, with the objective of showing how this dynamic deepens urban patrimonial inequalities. Through the use of social class segregation indexes and the net labor mobility balance, the impacts on housing prices are estimated using Geographically Weighted Regression (GWR) techniques. The results show that segregation favors middle and upper class housing, increasing their supply prices, while it reduces the value of lower class properties, thus intensifying the urban equity gap. Segregation is presented as a spatially heterogeneous phenomenon, where the positive and negative externalities of location reinforce the processes of socio-spatial differentiation. It is observed that, in popular sectors, the price of housing is negatively affected both by segregation and by its location with respect to employment sub-centers, while in privileged sectors the opposite occurs. The analysis also incorporates the notion of residential vulnerability, showing how low-income households face structural obstacles that limit the appreciation of their assets. In this context, the work provides interesting conclusions that coincide with the same evidence in the case of other cities, in the sense that residential segregation does not only act as a pattern of spatial distribution, but also as a mechanism that reproduces inequalities. In fact, the study concludes that the residential market in Bogota perpetuates historical inequalities through the differential valorization of space. Therefore, it is urgent to design urban policies that mitigate the effects of segregation, incorporating instruments that reduce fragmentation and promote a more equitable distribution of urban opportunities.

Next, Marín Villegas (Universidad San Sebastián, Chile) addresses the study of segregated housing developments in Colombia and Chile. Specifically, the paper analyzes residential satisfaction after the relocation of informal settlements in segregated social housing in Manizales (Colombia) and Concepción (Chile). Using a quantitative approach, differences in residential satisfaction are evaluated as a function of sociodemographic variables, considering dimensions such as housing, neighborhood and social environment. The results show that women have lower levels of satisfaction, which is attributed to a greater affectation by problems of mobility, insecurity and deterioration of social relations. It is also observed that household size has a negative influence on satisfaction with critically overcrowded housing. In terms of age, older adults show greater satisfaction, possibly due to a tendency to conformism over time. A positive relationship is found between income and housing satisfaction, suggesting that those with greater resources can improve their residential environment. This article explains how residential segregation not only affects the quality of life of those relocated, but also influences their perception of their new environment. Resettlement policies that consider factors such as gender, household size and the stability of community networks are suggested to improve the integration of affected populations.

Finally, with regard to the papers selected for the monographic section, the contributions are completed with the Nicaraguan case, it is addressed in the study presented by López Irias and Suárez Bonilla on urban fragmentation and segregation in the city of Managua. This article examines fragmentation and segregation in this urban area, contextualizing it within the transformation processes of Latin American cities. Based on a theoretical review of classical and contemporary models, it analyzes how recent urbanization has generated complex patterns of residential and socio-spatial segregation, combining dynamics of dispersion and concentration. The methodology employs a multiscale and comparative approach. The results show that the city has evolved towards a polynuclear configuration characterized by the creation of residential islands, commercial sub-centers and fragmentation of the urban fabric, favored by weak urban planning and real estate market dynamics oriented towards socioeconomic segmentation. Micro-segregation trends are identified, where physical proximity between social groups does not guarantee social integration. It also points to a displacement of popular sectors towards peripheries increasingly disconnected from urban opportunity areas. The study reveals that Managua reproduces and exacerbates socio-spatial inequalities through fragmented urban expansion patterns, driven by market dynamics and lack of comprehensive planning. It concludes that the fragmented city model in Managua represents a particular manifestation of the global processes of urban transformation, where the coexistence of spatial fragmentation and social segregation poses significant challenges for urban sustainability and territorial equity.

The set of articles gathered in this monograph allows for a comprehensive approach to the problem of urban segregation and fragmentation. As highlighted at the beginning of this presentation, contemporary socio-demographic and economic transformations have redefined and intensified spatial inequalities. Published research confirms that segregation is no longer just a question of income; it is also part of urban history, housing policies, suburbanization or gentrification, which help to explain the spatial distribution of different groups. One of the coinciding conclusions among the studies presented is the persistence and sometimes increase in socioeconomic segregation, even in contexts where ethnic segregation has been reduced. In addition, it is also generally perceived that high income segregation is presented with more notable intensities than segregation of less favored groups, which poses new challenges for urban inclusion. Research also suggests that fragmentation processes are not only the product of economic inequality, but also of symbolic and cultural factors that delimit the interaction between social groups in urban space. Finally, the articles highlight the importance of designing urban policies that are more equitable and sensitive to the different dimensions of fragmentation and segregation. Urban planning must integrate the social perspective and consider how mobility, housing and urban services can contribute to reducing territorial exclusion. In this sense, the monograph provides conceptual and empirical tools that can help us to better understand the complexity of segregation and fragmentation in cities at the beginning of the 21st century.

Complementarily, as indicated, this issue of Ciudades also includes a series of articles in its miscellaneous section, with other contributions that complement the interesting content of this issue of the journal. Specifically, five other articles are included on topics centered on the study of urban dynamics and phenomena such as accessibility, touristification, transitory settlements or the deficiencies of the urban habitat and the characteristics of housing in urban planning and urbanism.

The work of Valdivielso, Postigo and López-Escolano (University of Zaragoza) analyzes spatial inequalities related to accessibility and vertical mobility of the elderly in Zaragoza (Spain), addressing an aspect that has been little explored in urban planning. Using a geodemographic model based on the GIS integration of the municipal census and different official cartographic databases, the population aged 65 years and over residing in buildings of second floor or higher without elevator is located and characterized. The results reveal that 14.5% of the elderly population faces accessibility barriers in their homes, especially concentrated in older and lower income districts such as the neighborhoods of Delicias, Torrero-La Paz and Oliver-Valdefierro. In addition, aggravating factors such as advanced age, low educational level, residential isolation and lower income are identified. The spatial distribution of the affected population shows a strong concentration in certain urban blocks, evidencing a pattern of intraurban vulnerability associated with the obsolescence of the residential stock. The study stresses the need for comprehensive rehabilitation and accessibility policies that go beyond current ad hoc initiatives and promote inclusive urban environments, in line with the objectives of active aging and social equity. It also points out that the lack of vertical accessibility not only limits daily mobility, but also increases the risk of social exclusion and negatively affects the quality of life of the elderly. This work provides a replicable methodology for the spatial analysis of residential accessibility and proposes new lines of action for urban planning focused on improving the equity and autonomy of the aging population.

From another perspective, focused on the study of housing solutions in emergency cases, the work of Quiroz, Wagemann and Guzmán (Universidad Católica de Chile and Universidad Diego Portales, Chile) undertakes the study of the implementation of Emergency Transitory Neighborhoods (BTE) in Chile. The paper considers the main planning, design and management challenges that affect the effectiveness of emergency housing solutions after socio-natural disasters. Based on the review of international and national standards, the analysis of six BTE in the regions of Tarapacá and Atacama is presented, complemented with field work in two of the cases (Nantoco and Diego de Almagro). Shortcomings in land selection, construction quality, urban design and institutional monitoring are evidenced. The research shows that many BTE are located in risk areas, have deficiencies in community infrastructure and, far from being temporary solutions, evolve into semi-permanent settlements, prolonging housing precariousness. In addition, the spatial and social disconnection of these neighborhoods from the consolidated urban fabric is highlighted, fostering their stigmatization and marginalization. In contrast to international best practices, in Chile there persists a lack of adaptive planning and long-term vision for these settlements. The article proposes new urban design strategies based on three scales: the micro-scale (flexibilization of emergency housing and appropriate land selection), the meso-scale (functional organization of housing and creation of active public spaces) and the macro-scale (integration with the city and preservation of previous social networks). It emphasizes the need to strengthen inter-institutional coordination, update reference manuals and adopt comprehensive urban planning to prevent BTEs from perpetuating dynamics of urban precariousness and fragmentation. This study provides a replicable methodological framework for future transitional settlements and makes specific recommendations that seek to guarantee more dignified and sustainable transition processes for the affected communities.

Housing conditions are the protagonist of the study signed by Di Virgilio and Serrati (Universidad de Buenos Aires, Argentina), which reflects on how housing needs and habitat conditions act as structuring factors of the socio-spatial organization of Buenos Aires, the main urban conglomerate in Argentina. Through a methodology that combines social cartography, multivariate analysis and territorial clustering techniques, a housing deficit indicator is constructed that considers the material quality of housing, the degree of overcrowding, socioeconomic determinants and the characteristics of the urban environment. The results show a structural housing crisis affecting 54.2% of households, with strong disparities between the Autonomous City of Buenos Aires (CABA) and the 24 districts of the surrounding area. While in CABA 74.3% of households do not have deficits, only 34.5% in the conurbation are in this situation, with a predominance of needs for improvement and expansion. Six territorial profiles of deficit are identified, whose distribution evidences patterns of spatial inequality deeply rooted in historical dynamics and recent urbanization processes. The research stresses that the housing deficit must be addressed as a complex urban phenomenon, beyond its individual or building dimension, and calls for the design of comprehensive public policies that consider the articulation between housing, habitat and access to urban services. It also highlights the need to rethink intervention strategies to guarantee the right to housing and the city in contexts of profound heterogeneity and social fragmentation. The study provides an analytical tool that can be replicated in other Latin American metropolitan areas facing similar problems of socio-spatial inequality.

Turistification is addressed in the article contributed by Conejo, Nebot, Rosa and Gausa (University of Málaga and Universitá di Genova), analyzing this phenomenon in the historic center of Genoa (Italy). The research pays particular attention to the role of first floor activity in the processes of touristification of public spaces in historic port centers. Starting from the hypothesis that ground floor commercial and catering activity directly influences the transformation of public spaces, a methodology is developed based on indicators combining commercial gentrification and privatization of public space. Based on the analysis of 72 public spaces in the historic center of Genoa, four specific touristified areas are identified, characterized by high concentrations of commercial franchises, catering premises and intensive occupations of urban space through terraces and displays. The results show the overlapping of commercial and residential touristification in these areas, aggravated by the tourist pressure derived from the growing influx of cruise ships and the promotion of the city’s heritage. The study shows that touristification not only transforms the uses of public space, but also alters its accessibility and daily habitability, displacing traditional uses and local citizenship. It also identifies methodological limitations linked to the changing nature of the occupation of public space and proposes lines of future research, such as the analysis of temporary events and the incorporation of additional variables related to residential use. This research provides a replicable analytical tool to detect dynamics of touristification in other historic urban centers and provides relevant inputs to guide urban management strategies that seek to make tourism development compatible with the social and spatial sustainability of historic cities.

Finally, Lacilla, Ordeig and Bergasa (University of Navarra) consider the evolution of the integration of the single-family house in the urban design of Huesca (Spain) throughout the second half of the 20th century, within the framework of the concept of mixed development. Through a historical-urbanistic approach, different phases of the incorporation of the single-family house are examined, from its peripheral and segregated location to its full integration in urban projects of mixed design. The study distinguishes three major moments: a first stage of implementation of single-family detached housing in the urban structuring axes (Pamplona Blasco, Villa Isabel, Ciudad Jardín Ernesto Gil Sastre groups), a second stage of addition of single-family housing in residential estates originally planned for collective housing (Estates 25 and 28) and a third phase characterized by a typological integration from the origin of the urban design (Estate 24-II). The analysis reveals how the changes in general planning -especially the PGOU of 1958, 1980 and the Avance of 1994- had a direct impact on the evolution of the urban model, moving from a rigid functional zoning to a more complex and diverse planning. In addition, the transformations in the architectural, typological and functional characteristics of single-family dwellings are highlighted, as well as their progressive integration with public spaces and urban systems. The case of Huesca illustrates the transition from modernist seriation and segregation to a more articulated, adaptive and socially sustainable urbanism. This study contributes to understanding the processes of adaptation of contemporary Spanish urbanism to new social demands, offering a perspective that can be replicated in other intermediate cities.

Valladolid, May 2025