The use of anabolic steroids by both competitive and noncompetitive athletes has reached alarming proportions. Although use is most common in bodybuilders and weight lifters, athletes participating in track and field events and football also take the steroids. The recent resurgence in physical fitness awareness has only exacerbated the problem, and the physician needs to acknowledge the potential for abuse in any athlete. Despite the difficulties and ethical problems in designing good controlled studies with high-dose steroids, evidence suggests that steroids do increase muscular strength in certain subgroups of athletes. Unfortunately, numerous side effects and permanent damage may occur, and the athlete may be at risk for the development of fatal liver tumors or cardiovascular disease.