The twentieth century has seen immense worldwide shifts in population. Whether it is Europe to North America, the Caribbean to the United Kingdom, or East Asia to Australia, migration is one of the major factors that influences the global political and economic situation. By applying systematic theoretical frameworks to detailed empirical data, Worlds in Motion provides a unique overview of not only where migration occurs, and how it works, but crucially details the major factors that influence international population movement.

Illegal immigrants (and also legally present but illegally working immigrants) constitute a major issue in southern European countries through their large presence in the labour markets and their participation in (and hence perpetuation of ) underground economies. This comparative research gives a comparative analysis of southern Europe's immigration policies. The account of each country's pattern of informal employment of immigrants is located within a broader setting of contemporary southern European immigration controls and - in particular - of illegal, migration and employment in Europe....