Science advances better when we have a diverse research workforce; efforts to advance substance use research and addiction science are no different. Towards this advancement, and in response to PAR-19-246, we propose the Addiction Scientists Strengthened through Education and Training (ASSET) program designed to improve long-term engagement of a diverse addiction scientist workforce to meet the growing U.S. need for effective prevention and treatment of substance use disorders. ASSET Core Faculty who will mentor trainees are themselves diverse leaders in substance use research, from basic scientists to clinical researchers to public health researchers. Together we are well positioned to train future leaders in the field of addiction science, leaders who themselves will be empowered and inspired to provide education, mentorship and training to nurture future addiction scientists from underrepresented groups. Our proposed ASSET program will leverage existing San Diego State University (SDSU), University of California, San Diego (UCSD) educational resources and training capacity, along with mentorship from core faculty to support postdoctoral fellows, addiction psychiatry clinical fellows, and junior faculty in their professional growth to become independent substance use/addiction scientists and clinical researchers. Our program will include a two-level ‘mentoring the mentor’ component where faculty mentors will meet to discuss their mentorship experiences and coach each other on honing mentorship skills for diverse trainees. Trainees themselves will develop skills to overcome common barriers to research career growth. Our ASSET program will offer trainees a team of experienced and diverse mentors, coupled with an internship program with targeted training, research and funding opportunities focused on substance use and addiction science. Our specific objectives are to: 1. Develop a short-term (10-week) internship program (ASSET) with interdisciplinary research and career development training for URM postdoctoral fellows, clinical addiction psychiatry fellows, and junior faculty (trainees) who aspire to become independent researchers in addiction research; 2.Provide URM trainees with research knowledge, skills, and mentored career development training to become independent researchers and leaders in the field of substance use and addiction science, including ‘hard skills’ – manuscript writing, & grantsmanship to effectively and confidently design and conduct studies on substance use and ‘soft skills’ – network-building, negotiation, and managing issues commonly faced by URM investigators; 3.Train URM ASSET trainees in the responsible conduct of research with human subjects, with special consideration given to working with URM and disadvantaged populations in cross-cultural settings; and 4. Promote URM trainees’ transition to independent research by offering ASSET trainees peer-reviewed developmental ‘seed’ grants and travel grants for them to gain critical, hands-on, professional experience on formulation of a successful research proposal and ‘prime the pump’ in substance use research and addiction science.