This chapter explores the role of post-World War II immigration laws and policies of France, Germany, Great Britain, the Netherlands, United States, and Canada in giving rise to the mix of new social groups on their social landscapes. In one fundamental sense, the immigration regimes of European countries, the United States, and Canada are very much alike. All are restrictive in that they set limits on the numbers and type of people who can settle as permanent residents. There are, however, important transatlantic differences, lending some support to the common perception that Canada and the United States are more welcoming of immigration. Western European countries continue to be wary about immigration from outside of Europe. Their wariness is reflected in their attempts to make migration through marriages to the second generation more difficult as well as in immigration laws that constrain economic migration from the global South, keeping its numbers modest while seeking to select high human-capital immigrants.