TREATMENT DEVELOPMENT AND EVALUATION CORE - Project Summary Technology-delivered (web, mobile) interventions hold much promise for overcoming the substantial challenges that contribute to our population’s poor access to high quality, empirically-supported interventions for substance use disorders (SUDs) and related problems. Moreover, innovative technology-based behavioral interventions can likely increase the potency of existing interventions, in addition to extending their reach and reducing costs. Delivering on these promises has substantial public health implications, given that the majority of persons with SUDs are not receiving substance abuse treatment of any kind, and only the minority of those who do receive treatment are provided with an evidence-based intervention. The Center for Technology and Behavioral Health (CTBH) P30 Center was developed and funded by NIDA to enhance and expedite research efforts that leverage an array of technologies for improving treatment delivery systems. This P30 renewal proposal seeks to continue the mission of the CTBH, build upon successes, and enhance existing structure to meet the treatment and research communities’ needs. The Treatment Development and Evaluation (TDE) Core will continue to enhance the quality, efficiency, and impact of research projects among an interdisciplinary expert team focused on the development, efficacy, and effectiveness testing of innovative, science-based technology-based interventions. The TDE Core will continue to develop and expand activities and methods for sharing resources among CTBH affiliates and the greater scientific and clinical communities, and will improve and expand its TDE mentorship services for preparing competitive grant applications, including development of a new consultation service in novel methodologies for measurement and experimental design. The TDE Core will also continue to promote a better scientific understanding of how, and for whom, technology-based interventions are effective. Progress towards achieving this aim will be accomplished by expanding the Core’s coordination of cross-project studies, capitalizing on methodological advances in the field to answer scientific questions about predictors of intervention outcome and treatment engagement, in concert with mechanisms of change. These activities will advance the state-of-the science and practice of using technology-based interventions to optimize outcomes for SUDs and related problems.