Abstract. Mexican migration to the United States—one of the largest flows in human history—inverted in the late 2000s, and during the next decade more Mexicans returned home than those who migrated north. We exploit this historical reversal to estimate the effects of return migration on economic development in Mexico. We find that return migration leads to higher levels of development through improved income, labor, health, and educational outcomes. Our findings suggest that the benefits of migration extend beyond individuals’ tenure abroad, as accumulated capital, skills, and social norms have the potential to contribute to development back home.