Intensive socio-spatial differentiations are a characteristic trait of Latin American societies and have a powerful impact on land use patterns. In Chile, Santiago is a city that has been residentially segregated for a long time. Nevertheless, in the past two decades these patterns have been undergoing transformations on a geographical and a sociological scale showing ambivalent directions: On the one hand, forced segregation of economically disadvantaged residents, who remain concentrated on the urban fringe. On the other hand, ‘new spatial proximity’ due to voluntary segregation of welloff residents not located in their traditional areas of residence but rather closely to lower income neighbourhoods. In particular, the latter aspect is the focus of the ongoing research. The issue that new social and physical borderlines have emerged plays not only an important role for the social mixing of otherwise evenly poor areas, but also for new opportunities of socio-spatial integration processes as well which I consider as one path to diminish social vulnerability. Even though the debate about social integration by way of new spatial proximity in Santiago de Chile is still at the beginning of the generation of a theoretical model, its discussion is not new. Rather, there are many ambivalent and conflicting ideas about the relationship between segregation and integration into society. Some authors stated that there is no definitive relationship between integration and segregation; others discovered that the attributes of neighbourhoods and the experiences provided by neighbourhoods have profound effects on people’s capabilities and their ideas about what they can accomplish. As a result, such a concern with social mix has become common in a number of discussions. Several of them are related to neighbourhood diversity and neighbourhood effects on social opportunities of residents and others proposed the concept of ‘geography of opportunity’. But finally, all these discussions have one common question in mind: Do socially mixed neighbourhoods influence individuals’ opportunity? Or, could neighbourhood composition affect the opportunities for integration? Against this background, the PhD thesis is going to deal with these challenging overall research questions focussing on the effects of neighbourhood diversity and opportunities of social integration. It discusses the processes of desegregation in Santiago de Chile from the perspective of the contact hypothesis. This hypothesis suggests that even deep-seated antipathies and prejudice toward another group may be reduced by regular interactions which are seen as a precondition for a more tolerant society. In other words, people’s residences in relation to their immediate neighbours may tend to determine their lifeworlds, identities, and life chances. Therefore, the PhD thesis gives attention to the role of micro-ecological processes, in contrary to most methodological proposals on segregation which pay more attention to uneven distribution of social groups in residential spaces and less to their socio-spatial interactions in everyday life spaces. Based on these observations, I would like to seize the opportunity to discuss my theoretical approach as well as obtained research results on everyday life spaces of different socioeconomic groups in relation to social integration processes. I will address my presentation to (a) the theoretical model based on the discussion of related publications; (b) the methodological design and (c) the interpretation of both quantitative results of a household survey which I carried out in Santiago de Chile in November 2008 and qualitative results of interviews with experts and neighbours.