Many delinquent youth stop offending sometime in late adolescence or early adulthood. However, little is known about individual differences in desistance and which factors promote or inhibit desistance. In the current study, young males in the oldest sample of the Pittsburgh Youth Study were followed from ages 13 to 25. About one-third became persistent serious delinquents between ages 13 and 19. Out of that group, almost 40% desisted in serious offending between ages 20 and 25. Significantly more of the desisters, compared to the persisters in serious delinquency, had been employed or in school. Bivariate analyses demonstrated many predictors of desistance of serious delinquency in early adulthood in the domains of individual, family, and peer factors measured from early adolescence onward. Multiple regression analyses showed that the following promotive factors were associated with desistance: low physical punishment by parents in early adolescence and being employed or in school in early adulthood. The following risk factors were inversely associated with desistance during early adulthood: serious delinquency during late adolescence, hard drug use, gang membership, and positive perception of problem behavior in early adulthood. The article discusses the implications of promotive and risk factors for preventive interventions.