The population of Europe is rapidly diversifying, and it is now the case that not just major cities, but also small municipalities and authorities more and more frequently have local populations of a very wide range of ethnic, cultural and religious origins. Ethnic minorities, foreign residents, migrants, asylum-seekers, refugees and residents of migrant origin form a European population which is not only growing more strongly than in the previous decades, but has also become an integral part of the fabric of our societies. They are now a major force, thanks to their economic, social and cultural contribution.