Anabolic-androgenic steroids (AAS) have become more widely used and abused not only by elite athletes, but by nonathletes as well. It appears that these drugs are being used for cosmetic purposes as well as for promoting aggressive behavior. However, AASs may also be used in combination with other drugs such as ethyl alcohol and cocaine--a practice that may contribute to the observed increase in aggressive behavior. As there are no reliable animal models of AAS self-administration, it has been difficult to characterize the abuse liability and physical dependence potential of this class of drugs. A better understanding of neuroactive steroids, improved methods for assessing AAS abuse, and a revised interpretation of drug-seeking behavior is needed to develop improved treatment strategies for this emerging health-related problem.