ARREST AND CONVICTION RECORDS WERE EXAMINED FOR 15 FEMALE AND 42 MALE CLIENTS WHO HAD PARTICIPATED IN A METHADONE SUBSTANCE ABUSE PROGRAM. THE PROGRAM IS A LONG-RANGE PROCESS OF DETOXIFICATION AND REHABILITATION. THE PROGRAM IS INITIATED AT THE REQUEST OF THE CLIENT. THE DOSAGE OF METHADONE IS DECREASED ABOUT 5 MGS. MONTHLY, CULMINATING IN A PLACEBO FOR SEVERAL MONTHS, CONTINGENT UPON THE CLIENT'S SELF-REPORT OF WELL-BEING, AS WELL AS URINALYSIS RESULTS. CONCURRENTLY, THE CLIENT PARTICIPATES IN INDIVIDUAL AND GROUP COUNSELING, VOCATIONAL PLANNING AIMED AT TRAINING AND PLACEMENT, AND ADDITIONAL GROUP ACTIVITIES. THE ULTIMATE GOAL IS A DRUG-FREE STATE COUPLED WITH ECONOMIC INDEPENDENCE. SIX DEPENDENT VARIABLES WERE EXAMINED IN THE MIXED DESIGN: THE NUMBER OF MISDEMEANOR ARRESTS; MISDEMEANOR CONVICTIONS; FELONY ARRESTS; FELONY CONVICTIONS; TOTAL ARRESTS; AND TOTAL CONVICTIONS. EACH VARIABLE WAS MEASURED AT TIME I (DURING THE MONTHS IMMEDIATELY PRIOR TO PROGRAM ENTRY EQUIVALENT TO THE LENGTH OF TIME IN THE PROGRAM); TIME II (WHILE IN THE PROGRAM); AND TIME III (AFTER LEAVING THE PROGRAM). THE MOST SIGNIFICANT FINDING WAS THE ENORMOUS DECREASE IN FELONY ARRESTS AND CONVICTIONS FROM TIME I TO TIME II (ARRESTS DOWN 60 PERCENT AND CONVICTIONS DOWN 61 PERCENT); FROM TIME II TO TIME III (ARRESTS DOWN 87.5 PERCENT AND CONVICTIONS DOWN 100 PERCENT); AND FROM TIME I TO TIME III (ARRESTS DOWN 95 PERCENT AND CONVICTIONS DOWN 100 PERCENT). THE PROGRAM IS SPONSORED BY THE DETROIT MAYOR'S COMMITTEE FOR HUMAN RESOURCES DEVELOPMENT. TABULAR DATA REFERENCES ARE PROVIDED. (RCB)