Treatment of adolescents with alcohol use problems can be as successful as in adults, but the success often is short-lived, with most treated adolescents relapsing within a few months. Developmental differences among adolescents may contribute to this high rate of relapse, and treatment approaches that pay direct attention to the patients' developmental status may improve outcomes. To date, studies assessing adolescent alcohol treatment rarely have investigated the association between developmental stage and outcome. In addition, even experts do not fully agree on the developmentally appropriate outcomes that should be evaluated in adolescent treatment studies. Research methods and variables used to assess the outcome of adolescent alcohol treatment often rely on those used in treatment studies of adults. Developmental factors that may directly influence adolescents' amenability to treatment, such as pubertal status, psychological development (e.g., executive mental functions), social relationships, and developmental transitions, have not been adequately investigated. Studies using concepts from developmental science are needed to determine how individual characteristics, various contextual influences (e.g., from peers, family, or the social environment), and the interactions of these factors influence alcohol use behavior, amenability to treatment, and treatment outcomes. Knowledge gained in studies directly examining developmental factors should help in the design of more effective treatment programs with lower relapse rates.