This paper addresses the problem of undocumented immigration to the United States from Mexico, and current and proposed policies designed to control these undocumented flows. I summarize current U.S. policy toward undocumented Mexican immigration, which has been an expensive failure. I then take up three competing policy proposals: one pending in the U.S. Senate (S.1814 and S.1815) to expand the H-2A guest-worker program; one to construct a strict enforcement regime; and one based on linking U.S.–Mexican free trade to a free flow of labor. For each alternative, I predict likely outcomes and distributional consequences for seven types of actors (U.S. workers, U.S. consumers, U.S. employers, other U.S. citizens, undocumented immigrants, legal immigrants, and other Mexicans). I conclude that a binational approach to immigration control (a North American Common Market) is the most promising option, and I discuss its political feasibility.

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.