The advent of the twenty-first century marks a significant moment in the history of Latinos in the United States. The “fourth wave” of immigration to America is primarily Latino, and the last decades of the twentieth century saw a significant increase in the number of Latino migrants, a diversification of the nations contributing to this migration, and an increase in the size of the native-born Latino population. A backlash against unauthorized immigration, which may indict all Latinos, is also underway. Understanding the growing Latino population, especially its immigrant dimensions, is therefore a key task for researchers in the social sciences and humanities. The contributors to Immigration and the Border address immigration and border politics and policies, focusing on the U.S. side of the border. The volume editors have arranged the essays into five sections. The two chapters in the first section set the stage and discuss the binational lives of Mexican migrants; chapters in the subsequent sections highlight specific political and policy themes: civic engagement, public policies, political reactions against immigrants, and immigrant leadership. Because the immigration experience encompasses many facets of political life and public policy, the varied perspectives of the contributors offer a mosaic that contextualizes the impact of and contributions by contemporary Latino immigrants. Their research will appeal not only to scholars but to policymakers and the public and will inform contentious debates about migration and migrants.