Abstract This R25 application seeks renewal of the national Diversity in Addiction Research Training (DART) program (DA020537-16; formerly the Drug Abuse Research Training program), designed to address the persistent scarcity of physicians and diverse clinical researchers engaged in addiction research. Greater diversity cultivates robust learning environments, promotes a broad array of ideas and perspectives thereby enhancing innovation, and promotes culturally competent care to help eliminate racial/ethnic health disparities in addiction. The DART program was initiated in 2006 at the Medical University of South Carolina (MUSC) with a primary focus on psychiatry residents and has since expanded to include a vibrant summer research program, which enrolls trainees from national and international institutions at the undergraduate, graduate, and medical student educational levels. DART provides an intensive core research training curriculum including a weekly seminar series, mentored hands-on research experience, an individualized training plan, and formal near-peer mentoring. To date, 220 trainees have enrolled in DART and retention is excellent (only one trainee has dropped out). Program evaluation data demonstrate that the majority of trainees remain engaged in research post-DART, and trainees have been highly productive, generating 575 conference presentations and 353 manuscripts. During the next five years, we will significantly expand and innovate the DART program and enhance the diversity of trainees and faculty through new partnerships with external residency programs. We have established new partnerships with Howard University and the University of Virginia, and plan to expand to additional residency programs during the renewal period. In addition, we have assembled an outstanding Advisory Board comprised of 16 diverse (67% underrepresented racial/ethnic minority [URM] faculty and 72% women faculty) and highly accomplished researchers, educators, and leaders in the field from 14 different institutions who will bring exceptional talent and diverse experiences, viewpoints, and areas of expertise to the DART program by providing input, seminars, mentoring, and one-on-one career advice. We have augmented the curriculum in the areas of (a) opioid use disorders, (b) remote/virtual clinical trials, and (c) health disparities in addiction, supported by collaboration with the NIDA Office of Diversity and Health Disparities. During the renewal period, we aim to enroll 122 trainees with at least 50% or more URM trainees. Dr. Colleen Halliday, a faculty member at MUSC with expertise in racial/ethnic disparities in substance use and mental health outcomes, joined the DART Leadership Team in 2020 and will help guide targeted recruitment efforts to further enhance trainee diversity. This application aligns with the NIH UNITE Initiative to support diversity, equity, and inclusion in the biomedical workforce and is directly responsive to the new NIDA Racial ...