Substance use among youth remains a major public health problem. About half of all 12th graders have tried an illicit drug and over 72% of this same age group has used alcohol. Rates of abuse of prescription opioids among youth are estimated to have increased about 542% in the past decade. Although effective substance abuse treatment programs for youth exist, they are currently of limited reach. Only 1 in 10 adolescents who need substance abuse treatment receive any care. The limited compatibility of research-based interventions with treatment agency realities may present numerous operational barriers to the transfer of evidence-based practice into community-based settings. An interactive, computer-delivered psychosocial intervention has the potential to address these challenges, as it allows for complex interventions to be delivered at a low cost, without increasing demands on staff time or training needs. It may also be highly acceptable to youth and enable widespread dissemination of science- based treatment in a manner that ensures fidelity. In this application, we propose to develop and evaluate the efficacy and cost-effectiveness of an evidence-based, computer-delivered, psychosocial intervention for adolescents in treatment for substance use disorders. To our knowledge, the planned program will be the first interactive program to provide comprehensive, psychosocial substance abuse treatment to adolescents via computer-based technology. AIM 1: Develop an interactive, computer-delivered, psychosocial treatment for adolescent substance use disorders, which will be grounded in the Adolescent Community Reinforcement Approach (A-CRA), a behavioral treatment for adolescents of demonstrated effectiveness and cost-effectiveness. AIM 2: Evaluate the efficacy of the computer-delivered intervention with adolescents in outpatient treatment for substance use disorders. Adolescent participants in a controlled trial will be randomized to (1) therapist-delivered A-CRA, (2) computer-delivered A-CRA or (3) standard treatment. We will evaluate the relative efficacy of these interventions on the primary outcome of objective substance use and secondary outcomes of treatment retention, self-reported drug use, HIV risk behavior, therapeutic alliance, psychosocial functioning, and the extent to which participants report their treatment needs are adequately met. AIM 3: Perform a comprehensive economic analysis to provide necessary information to inform a decision regarding adoption of this new therapeutic tool. We will estimate a societal incremental cost- effectiveness ratio (ICER) to inform an adoption decision from a societal perspective, as well as the cost- effectiveness to inform an adoption decision at the program level. These detailed cost data will be vital to future translational projects to disseminate effective computer-based behavioral models to community systems. PUBLIC HEALTH RELEVANCE: To our knowledge, the program we propose to develop will be the first interactive program to provide comprehensive, science-based psychosocial substance abuse treatment to adolescents via computer-based technology. The planned program will be browser-based and can be delivered via Internet, intranet or CD- ROM, allowing for its use in a wide variety of settings, including treatment programs, home, community organizations, schools, emergency rooms, and health care providers'offices. The proposed research will contribute new empirical information relevant to increasing the delivery of evidence-based psychosocial treatment to adolescents with substance use disorders in a manner that is cost-effective and will promote the adoption of effective treatment.