This chapter reviews the development of integration policies of European cities since the 1970s. The analysis shows a convergence: while originally only levels within the national context were relevant, since 2000 both horizontal, transnational relations between cities and vertical relations with the EU became important. Further, cities have developed diverse answers to integration in the legal-political, the socio-economic and the cultural-religious dimension. Divergence in local integration policies is caused by the institutional context and the characteristics, efforts and abilities of the migrants concerned. While cultural diversity and interculturalism have become key concepts, most efforts at the local level continue to be directed at the legal-political and, above all, the socio-economic integration of immigrants.