THE COHORT STUDY IS BASED ON THE YEARS 1969 THROUGH 1974. ARTC HAD A CONTRACT TO PROVIDE METHADONE MAINTENANCE AND TREATMENT TO SELECTED PERSONS ARRESTED FOR DRUG-RELATED OFFENSES PLUS OTHERS WHO WISHED TREATMENT. THE ADMISSION POLICY WAS NONRESTRICTIVE AND THE CRITERIA FOR CONTINUATION WERE MUCH LESS STRICT THAN FOOD AND DRUG ADMINISTRATION GUIDELINES. THE COHORT STUDY SHOWED THAT 37 PERCENT OF PATIENTS DROPPED OUT IN THE FIRST YEAR, 24 PERCENT DROPPED OUT BETWEEN 13 AND 24 MONTHS AND 23 PERCENT STAYED 36 MONTHS. HOWEVER, AMONG PATIENTS IN THE FIRST COHORT (THOSE WHO BEGAN TREATMENT IN 1969) ONLY 24 PERCENT TERMINATED IN THE FIRST YEAR, WHILE 48 PERCENT OF THOSE IN THE THIRD COHORT DID SO. ABOUT 38 PERCENT OF PATIENTS MISSED MEDICATION MORE THAN A QUARTER OF THE TIME IN THE FIRST YEAR. THERE IS AN INVERSE RELATIONSHIP BETWEEN MISSED MEDICATION AND PROGRAM RETENTION; 37 PERCENT OF THOSE WHO TERMINATED WITHIN THE FIRST 12 MONTHS MISSED MEDICATION A QUARTER OF THE TIME OR MORE, WHILE ONLY 9 PERCENT OF THOSE WHO STAYED 36 MONTHS DID. MISSED MEDICATION GREW INCREASINGLY WORSE WITH EACH TREATMENT COHORT. VALIDITY OF THE 'MORPHINES IN URINE' TESTING IS QUESTIONABLE. HOWEVER, FOR THE FIRST COHORT, IN WHICH RESULTS SEEM TO BE MOST COMPLETE, 46 PERCENT OF THOSE RETAINED 12-12 MONTHS, 24 PERCENT OF THOSE RETAINED 13-24 MONTHS, 22 PERCENT OF THOSE RETAINED 25-36 MONTHS, AND 21 PERCENT RETAINED MORE THAN 36 MONTHS HAD POSITIVE MORPHINE IN MORE THAN HALF OF URINES TESTED. THE EMPLOYMENT PICTURE GREW LESS FAVORABLE BY COHORT. OVERALL, 44 PERCENT OF PATIENTS DID NOT WORK AT ALL DURING THE TREATMENT PERIOD, 30 PERCENT WORKED FOR LESS THAN 6 MONTHS, AND ONLY 13 PERCENT FOR MORE THAN A YEAR. THE PROGRAM SHOWED SLIGHT CORRELATION WITH DECREASE IN CRIME RATE. BEFORE ENTRY THE MEAN CHARGE RATE WAS 87 OR ABOUT 4/5 OF A CHARGE PER PATIENT PER YEAR. THIS ROSE DRAMATICALLY JUST BEFORE ENTRY TO 137. CHARGE RATE AFTER ONE YEAR OF TREATMENT WAS 119, AFTER 2 YEARS 96, AND AFTER 3 YEARS 56. THE MAJOR PORTION OF THE DECREASE WAS DUE TO FEWER DRUG CHARGES. IT IS SUGGESTED THAT THE REASON THE PROGRAM SHOWS PROGRESSIVELY LESS FAVORABLE STATISTICS WITH EACH TREATMENT COHORT IS THAT THE ADMINISTRATION WAS VERY LENIENT. PATIENTS SOON BEGAN TO JUST 'DROP IN' FOR THE METHADONE, MISSING THE SUPPORTIVE SERVICES WHICH WERE INTENDED TO BE AN INTEGRAL PART OF THE PROGRAM. TWO OTHER PROBLEM AREAS ARE THE POSITIVE MORPHINE MEASURES AND THE FACT THAT ONLY 13 PERCENT OF EMPLOYED PATIENTS SAID THE PROGRAM HAD BEEN HELPFUL IN FINDING A JOB. APPENDIXES CONTAIN A BIBLIOGRAPHY, DATA ON RESEARCH METHOD, AND ADDITIONAL STATISTICS.