For almost half a century, scholars and policy makers in the United States have emphasized the negative effects of residential segregation for social and economic advancement of the urban poor. Policies to fight segregation have however shown limited success and notably met the resistance of immigrant minorities. The present book adopts a new perspective and examines under which conditions segregation facilitates or hinders the building of social and other assets or capital of immigrants. Analyzing experiences with ethnic clustering of Mexicans in St. Paul, Minnesota, it calls for pluralistic housing policies to accommodate the increasingly multicultural urban realities in the US.