Abstract This chapter examines new forms of social segregation in Italy’s economic capital, Milan. Over the last three decades, processes of deindustrialisation and urban regeneration associated with the arrival of large inflows of migrants have been the most dynamic trends, and the largest contributors to recent territorial and demographic changes. During this period important qualitative and quantitative population changes have occurred in Milan’s urban region, particularly in terms of the characteristics and directions of migratory flows, and the ethnic and social structuration of metropolitan areas. In this chapter, segregation in the city of Milan is addresed using segregation indices, dissimilarity indices, indices of relative concentration, indices of isolation and a factor analysis. Special emphasis is given to the relationship between urbanisation and the social division of space, and the relationship between ethnic and social segregation for the period 1991-2011. As a tentative conclusion we provide a number of explanatory hypotheses concerning the changing nature of segregation in Milan.