The Indigenous people of the Americas experience persistent and dire health disparities related to HIV/AIDS. Despite the glaring disparities, there is a paucity of culturally grounded research addressing their biomedical and socio-behavioral health concerns. A strong network of highly trained Indigenous scholars dedicated to culturally relevant HIV prevention research would contribute to ameliorating HIV-related health disparities among Indigenous people. This competitive renewal application, in response to PAR-17-485: NIMH Research Education Mentoring Program for HIV/AIDS Researchers (R25), proposes a third iteration of the Indigenous HIV/AIDS Research Training Program (IHART). IHART3-Itza will develop a cadre of culturally grounded Native scholars capable of serving as PIs on extramurally funded HIV/AIDS-related prevention and disparities studies with Indigenous populations. The IHART3-Itza program is based on the success of the first 10 years of IHART (IHART and IHART2-Lauhoe), the only Native-specific HIV/AIDS research education mentorship program in the US. IHART3-Itza extends the reach of the original IHART programs from American Indians/Alaska Natives, Native Hawaian/Pacific Islanders, underrepresented racial/ethnic groups, and non-Natives working in Indian Country to include as well the historically underserved Indigenous Latinx Populations (ILP). ILP include people originally or descended from Indigenous communities in Mexico and Central and South America. Whereas IHART2 focused primarily on newly postdoctoral scholars, IHART3-Itza will target more experienced early- stage investigators (5-10 years post-Ph.D.) interested in developing novel expertise in HIV prevention research. Finally, the program will target recruitment of scholars residing in or working in the US HIV hot spot regions of the Southeast and West. IHART3-Itza will continue to employ a successful 360 degree co- mentorship approach with flexibility for program Fellows and Mentors to co-identif