The addiction and conviction status of 60 male patients, examined at a London drug clinic in 1970 was reassessed at four-year follow-up. Forty-three per cent had become abstinent, 23 per cent remained dependent and 15 per cent had died. Ninety-seven per cent had received a court conviction and 73 per cent were convicted during follow-up. A prognostic assessment was determined in combined terms of continued addiction and continued delinquency. Poor outcome related to a lack of educational attainment, earlier first conviction and regular opiate use on arrival, and was associated during follow-up with an irregular clinic attendance beyond one year, drug conviction and death. Good outcome related to an absence of parental loss and later first conviction, and was associated during follow-up with discharge within one year without hospital admission. Analysis of the data indicates the value of combining forensic information with drug history in prognostic assessment.