In brief: This article presents a review of the literature on drug misuse by athletes and information from 16 sports and medical organizations whose representatives met in 1985 to discuss the problem. Studies of drug use by athletes are relatively few. Existing data do not show a difference in drug use between athletes and nonathletes, but anabolic steroids probably are used more widely among athletes. Our review disclosed little evidence that drugs can improve an athlete's performance without also posing the threat of serious harm. Major sports organizations have banned the use of anabolic steroids, stimulants, diuretics, analgesics, beta-adrenergic blockers, cocaine, marijuana, and heroin, and some have begun testing athletes. Physicians should assist efforts to prevent the illegal distribution of drugs and should help with existing education and testing programs.