| The end of the cold war has witnessed two striking sociological phenomena: unprecedented mass migration to the core countries---U.S. and Western Europe---and eruption of racial/ethnic conflict throughout the Globe. This work analyzes the causes of increasing racial/ethnic tensions occurring in the core countries, with particular attention to the metropolitan areas of the U.S. and Italy.;The main argument is that the postindustrial economy features new patterns of socio-economic inequality that are expressed by the unequal distribution of socio-economic resources and minorities between the urban core and surrounding metropolitan periphery. In addition, contemporary migration flows differ markedly from previous periods due to their national origins---no longer Europe---and their preferred destination---no longer the central cities of major metropolitan areas. The combined impact of these phenomena is redefining racial/ethnic relations which are becoming a complex social configuration of increasingly heterogeneous minority groups. |