Center for Comparative Immigration Studies

With nearly one in ten residents of advanced industrialized states now an immigrant, international migration has become a fundamental driver of social, economic, and political change. We review alternative models of migratory behavior (which emphasize structural factors largely beyond states’ control) as well as models of immigration policy making that seek to explain the gaps between stated policy and actual outcomes. Some scholars attempt to explain the limited efficacy of control policies by focusing on domestic interest groups, political institutions, and the interaction among them; others approach the issue from an international or “intermestic” perspective. Despite the modest effects of control measures on unauthorized flows of economic migrants and asylum seekers, governments continue to determine the proportion of migrants who enjoy legal status, the specific membership rights associated with different legal (and undocumented) migrant classes, and how policies are implemented. These choices have important implications for how the costs and benefits of migration are distributed among different groups of migrants, native-born workers, employers, consumers, and taxpayers.