This paper examines the association of psychosocial factors and long-term drug use behaviors (year-5.5) among adolescents with a substance dependence disorder. One group received treatment with a 12-Step approach (n = 159) and one group was on a waiting list (n = 62). Four psychosocial factors (deviant behavior, peer drug environment, psychological disturbance and family estrangement), as measured by a standardized self-report questionnaire, were examined as predictors across three time points (year-1, year-4 and year-5.5). Improved outcome across time was significantly associated with decreases in deviant behavior, peer drug environment and family estrangement. However, psychological disturbance was not associated with outcome. Also, we did not find an effect on outcome as a function of age, gender and race. Youth that received treatment, as opposed to the waiting list youth, generally revealed a more favorable outcome across time. Treatment implications of the study findings are discussed. (Contains 4 tables and 2 figures.)