Substance use problems and HIV/AIDS disease are complex disorders that affect the health of disadvantaged racial/ethnic minority groups, largely due to significant health disparities. To make significant progress in identifying the underlying causes of these diseases and improve their diagnosis, prevention, and treatment requires the work of a transdisciplinary team of researchers united by a common mission, supported by a connected infrastructure, and working in a geographical location ideally suited for the study of the targeted diseases and disparities. The proposed RCMI, will bolster critical infrastructure, technologies, collaborations, recruitment of new minority faculty, and professional development of minority faculty already at Florida International University (FIU), to meet the challenges of improving the health of traditionally underrepresented groups and reduce health disparities. FIU is among the 10 largest universities in the US with a diverse student body of nearly 50,000 students, including 61% Hispanic, 15% non-Hispanic white, 13% non-Hispanic black, 4% Asian, and 7% other minority groups. There are 256 early stage minority faculty in various disciplines related to health disparities in HIV or substance use problems. FIU has demonstrated an extraordinary support for developing the next generation of health disparity researchers with institutional support to diversify faculty and promote equity at FIU. The activities of this proposed RCMI will provide research opportunities, mentoring from numerous senior, NIH-funded investigators, infrastructure that includes laboratories, clinical spaces, and behavioral studies, imaging studies, Biostatistics and Bioinformatics support. Educational opportunities will include seminars, colloquia, journal club, lectures, mini-courses and mentorship committees. Training in responsible conduct of research is mandatory for all senior and junior investigators. The RCMI and FIU?s Office of Research and Economic Development (ORED) will assure inclusion and integration of infrastructure, prioritize resources to make facilities available, provide assistance to meet requirements for institutional compliance, support operation, administration and research activities and devise plans for sustaining research infrastructure through cost recovery. The training provided by this RCMI will enhance the diversity of the research enterprise and will offer mentoring opportunities on community engagement, recruitment of minority populations, and addressing the mechanisms by which health disparities and differences in health outcomes negatively affect racial and ethnic minorities.