Subjects in the aftercare arm were treated immediately following intensive inpatient or day-hospitalizations. Subjects were selected in this way to accommodate the ongoing practice of clinical research units to specialize in either outpatient or aftercare patients, and to increase the generalizability of findings to anyone with alcohol-related problems. Participants did not differ on treatment assignment, assessment, matching hypotheses, or analytical strategies as a function of which arm they were in. All study participants met the following inclusion criteria: 1) met DSM-III-R criteria for alcohol dependence or abuse, 2) listed alcohol as their principal drug of abuse, 3) were at least 18 years old 4) had been drinking for the three months prior to their participation, 5) had a 6th grade reading level or better, and 6) were free of probation or parole requirements that would interfere with participation. Exclusion criteria for Project MATCH included the following (Project MATCH Research Group, 1993): 1) meeting DSM-III-R criteria for dependence on sedative/hypnotics, stimulants, cocaine, or opiates or if they had taken any of these substances intravenously in the last 6 months, 2) current danger to self or others, 3) lack of prospects for residential stability, or inability to verify a place of residence
