This paper investigates the impact of legalization on the economic outcomes of the legalized population. It uses a natural experiment caused by the 1986 Immigration Reform and Control Act (IRCA) which gave amnesty for undocumented immigrants who could prove continuous residence in the U.S. after January 1, 1982. The arbitrary cutoff date on the eligibility criteria causes a discontinuity in the relationship between the year of immigration and the probability of being legal. This paper uses this discontinuity to identify the causal impacts of legalization on immigrants' outcomes. Regression discontinuity and difference-in-differences estimates show that immigrants eligible for the policy have a significantly higher probability of being naturalized citizens than those who were not. Legalization is also found to have a positive and significant effect on wages, a negative effect on the probability of working in a traditionally illegal occupation, and no significant effect on geographical mobility. The analysis for different demographic groups confirms such conclusions and shows that the estimated effects of legalization are larger for low-educated Latin American immigrants, the group that was disproportionably affected by the policy.