As it continues to grow, the composition of the Hispanic population is undergoing a fundamental change: Births in the United States are outpacing immigration as the key source of growth. Over the next twenty years this will produce an important shift in the makeup of the Hispanic population with second-generation Latinos–the U.S.-born children of immigrants– emerging as the largest component of that population. Given the very substantial differences in earnings, education, fluency in English, and attitudes between foreign-born and native-born Latinos, this shift has profound implications for many realms of public policy, and indeed for anyone seeking to understand the nature of demographic change in the United States.