We draw upon the 3-wave longitudinal dataset called Welfare Children and Families: A Three-City Study to examine the long-term implications for adolescents and young adults (N=783) of mothers' welfare receipt and labor force participation from 1999 to 2005. In general, changes in mothers' work and welfare patterns were not associated with deterioration or improvement in youth development (ages 16 to 20 years at wave 3). The few significant associations suggested that youth whose mothers increased employment (net of welfare participation) were more likely to show declines in serious behavior problems and delinquency compared to youth whose mothers were unemployed or employed part-time during the study period. Welfare roll exits (controlling for employment experiences) were unrelated to adolescent and young adult outcomes. Mothers' employment transitions were linked to improvements in household income and mothers' self esteem in addition to reductions in financial strain and their own illegal activities. However, these associations did not explain the relation between maternal employment and youths' improved behavior. These results do not support the predictions of either the supporters or the opponents of welfare reform, an outcome we discuss.