The high prevalence of alcohol and substance abuse by adolescents poses a significant threat to the wellness of youth. Adolescents appear to use drugs for a variety of reasons. In addition to the multiple etiologic and risk factors present for substance abuse, there are many pathways teenagers may follow on their way to substance abuse. The prevention strategies which appear to be most effective utilize a social influence approach or emphasize personal and social skills teaching. Prevention programs which promote resisting social influences help adolescents identify and resist specific social pressures to adopt behaviors by informing them about health and social consequences; identifying peer, media, and environmental influences; modeling responses to these influences; role playing; and goal setting. There may be a prophylactic effect to minimal exposure to substance abuse risk factors that may inoculate an adolescent against using drugs. If drug-using behavior is not learned during adolescence due to infrequent exposure to risk, there may be a good chance that drugs will never be used. Many of the program evaluations and research studies conducted so far have some methodological shortcomings. Future studies need to standardize the definition of drug use, include appropriate control groups, and correct for the confounding effects of variables associated with drug use attitudes, behaviors, and risk factors. (ABL)