• A sample of 3,131 persons from approximately 25,000 admitted to drug abuse treatment programs in the Drug Abuse Reporting Program during 1969-1972 were followed up in 1975-1976. Treatment groups included methadone hydrochloride maintenance, therapeutic community, outpatient drug free, outpatient detoxification, and a comparison group that completed intake but did not enter treatment. Outcome criterion measures (drug use, employment, criminality, and treatment readmissions) based on the first year after treatment were more favorable in the methadone maintenance, therapeutic community, and outpatient drug-free groups than in the outpatient detoxification and intake-only groups. Evaluation of differential outcomes and their relationships with pretreatment and duringtreatment measures within each group indicated that pretreatment criminal history, during-treatment performance, and length of time in treatment were significantly related to posttreatment outcomes.