Citizenship implies exclusion of non-members. Migrations, processes and policies of first admission and incorporation of ethnically and culturally diverse newcomers are among the most hotly contested political issues, especially in a world of gross inequalities. This comparative and interdisciplinary collection sees distinguished moral and political philosophers, historians, sociologists, anthropologists and political scientists from America, Australia and Europe criticize existing institutions and increasingly restrictive policies and look for alternatives more in line with principles and constitutions of liberal democratic welfare states.