This study investigates how drug use in adolescence contributes to socioeconomic outcomes in young adulthood. Several studies have investigated whether drug problems alter the life course in ways that are detrimental to young adult achievement, but findings are inconsistent. We use data from the National Longitudinal Study of Adolescent Health to investigate this issue. Results show that drug use in adolescence is significantly related to achievement outcomes by young adulthood, though not always in ways that might be predicted. Specifically, where significant, alcohol use is associated with greater socioeconomic achievement by young adulthood, whereas illegal drugs are associated with decreased socioeconomic achievement. Tests of potential mediators largely did not change this relationship. Implications of the results are discussed. (Contains 3 tables.)