PROJECT SUMMARY: This application represents the first renewal request to continue support of the UCLA Predoctoral Training Program in Brain and Behavioral Development during Adolescence (UCLA BBDA). UCLA BBDA leverages UCLA’s internationally known strength in adolescence by integrating campus expertise in developmental neuroscience and behavioral science to create a one-of-a-kind training experience that produces translational scientists with the skills necessary to conduct research supporting the NICHD mission to “enhance the lives of children and adolescents, and optimize abilities for all.” The study of adolescent brain development has expanded dramatically over the past two decades, and UCLA BBDA training focuses on three substantive growth areas necessary for the field to have translational impact and improve the health and lives of the nation’s youth: (1) an integrative approach that incorporates both typical and atypical brain development; (2) the interaction between brain development and the social environment; and (3) sophisticated approaches to examining longitudinal change over time. We accomplish this by providing an intensive mentored research experience, dedicated coursework designed for the program, access to cutting-edge faculty and research centers, as well as comprehensive professional training that provides trainees with the toolkit necessary to become productive and impactful independent scientists. As described in the Progress Report, we have had a successful first five years with 19 trainees working with 14 different primary and secondary mentors and who have demonstrated a strong level of productivity. All five who have received their Ph.D. have obtained post-doctoral, research, and faculty positions and the remainder are on track to complete their Ph.Ds in a timely fashion. In the next five years, we aim to build upon our earlier successes and develop the program further by adding new faculty and incorporating access to other resources on campus in order to provide additional training opportunities in: (a) advanced methods in neuroimaging, such as structural and functional brain connectivity; (b) biological markers of health; and (c) effective translation and dissemination of the science of adolescence. Collectively, these enhancements will help prepare our predoctoral trainees to position themselves at the leading edge of the field and establish independent research careers that will further NICHD’s mission of enabling children and adolescents to lead healthy and optimal lives.