This project deals with urban and social problems of public house neighbourhoods, in particular large (public) housing estate neighbourhoods built in the metropolitan areas of Lisbon and Oporto between the 1970s and the early 2000s. Most of these large housing estates were built in the framework of Keynesian welfare state, incorporating principles of igualitarianism, functionalism and social change through state determined planning, even in cases – such as Portugal – where the construction took place in the postkeynesian period (after the late 1970s). This process has frequently produced new “neighbourhoods”, characterized by large groups of buildings distinct from the surrounding elements, both physically and socially. Although built within the social justice principles of social democrat Keynesianism and a planning philosophy of modernism, several of these housing estates progressively started to concentrate a myriad of urban and social problems. Although we can find substantial literature on the nature of such problems, there is not a model that successfully combines the various explaining factors. Issues such as socio-spatial stigmatization and relative isolation, poor quality of the public space, deficient urban design, lack of urban functions such as retail or economic services, socio-ethnic segregation, employment precarity, limited responses from schools as well as deficient management systems have all been considered key-elements to understand the problems emerging in this kind of neighbourhoods. In Portugal, only recently the policy principles orienting rehousing strategies and public housing options started to change in order to incorporate new orientations such as social mix and geographical dispersal of the public housing blocks. Nevertheless, new large public housing estates were built in the late 1990s under the rehousing programme PER. In several of these large housing located in the metropolitan areas of Lisbon and Oporto, the aforementioned problems have been identified in scientific and technical researches as well as widely spread by the media (for instance, in 2008 summer several news about riots and vandalism in such neighbourhoods). This project is focused in two key research questions:1) Which regeneration solutions can be implemented in the large “problematic” housing estates of public promotion? 2) Are the present rehousing solutions involving geographical spreading and social mix more efficient than the past ones? And two complementary goals: 1) To identify critical success (or failure) factors associated to public housing policies (and public space policies) targeting large housing estates; 2) To discuss the challenges associated to the overrepresentation of populations with specific housing needs (Gypsies, immigrants) in these housing estates.