The study proposed is a critical phase of the Treatment Outcome Prospective Study (TOPS): a long term, large-scale longitudinal investigation of the natural history of drug abusers before, during, and after receiving services in federally funded drug abuse treatment programs. A total of about 11,000 clients were included in three cohorts, 1979-1981. These clients were interviewed quarterly while they remained in treatment. To date, posttreatment studies (3 months, 1 year, and 2 years after termination) of the 1979 admission cohort and the 1980 admission cohort have been designed and implemented. This grant application proposes to complete the prospective cohort design of the TOPS research program by conducting a posttreatment study of the 1981 TOPS admission cohort. The study will describe client outcomes in the first years immediately after leaving treatment and identify social, economic, and behavioral factors which, combined with the treatment experience, are associated with clients developing socially productive lifestyles. The specific objectives of the followup study of the 1981 TOPS admission cohort are to . describe the posttreatment behavior of clients in the 1981 TOPS admission cohort to a point up to 3 years after leaving the TOPS drug treatment program, . complete the prospective cohort research design of TOPS to permit trend analyses of outcomes for the 1981 admission cohort and to compare outcomes among the 1979, 1980, and 1981 admission cohorts, and assess the posttreatment behavior of clients in the seven programs in Detroit and Philadelphia which were not included in 1979 and 1980 TOPS Intreatment and Followup data collection. In addition, the followup study being proposed provides options to collect and analyze data for five special substudies of criminal justice system clients, depression, diagnosis of mental health, perceptions of neighborhood, and impacts of closing methadone programs.