Abstract: RUSTBELT CFAR Developmental Core B Revision Hispanic/Latinx people are disproportionately affected by HIV: In 2021, according to the Centers for Disease Control, Hispanic/Latinx persons made up 18% of the population of the United States but accounted for 29% of new HIV diagnoses. Hispanic/Latinx men who have sex with men (MSM) accounted for 33% of diagnoses among all MSM. In Puerto Rico (PR), there are currently 15,801 people living with HIV. San Juan, the capital of PR, is a Phase 1 Priority Jurisdiction identified in the Ending the HIV Epidemic (EHE) Initiative. Latinx people in PR have an estimated lifetime risk for HIV infection of 2.08% (1 in 48), higher than the lifetime risk for HIV diagnosis among Latinx people in the continental United States (1.92%;1 in 52). Furthermore, the estimated HIV prevalence in the general adult population in PR is nearly 1.1%, and 7.3% among sexual minority men. PR also has one of the highest levels of HIV status unawareness among sexual minority men, and the lowest pre-exposure prophylaxis uptake reported in the United States. Greater diversity in the healthcare workforce is an important strategy to address racial and ethnic healthcare disparities. The Rustbelt CFAR proposed to develop education and training pathways for Puerto Rican students to become scientists or physician-scientists engaged in HIV/AIDS research. The Rustbelt Investigators for the Next Generation (RING) Program was first developed and funded in 2022/23 in response to the NIH supplement request for CFAR Diversity, Equity, and Inclusion Pathway Initiatives (CDEIPI). The objectives of the RING Program are (a) to provide a 10-week summer mentored research-training experience in HIV/AIDS for 10 undergraduate and/or masters students from the University of PR (UPR) at Case Western Reserve University (CWRU) or the University of Pittsburgh (Pitt); (b) to provide career development activities, including weekly seminars led by outstanding faculty leaders and training in techniques in the Rustbelt CFAR laboratories and core facilities that lead to research careers in HIV; and (c) to evaluate the scholars’ attitudes about engaging in a research career in HIV before and after participation in the RING Program. The goal of the new Rustbelt CFAR-PREP is to enhance the pool of PR students who complete PhD degrees in HIV/AIDS. Considerations driving the development of the Rustbelt CFAR PREP included: (a) while research opportunities exist in the UPR system, they often lack the depth, breadth and rigor of those on the mainland, leaving students under-prepared for graduate school; and (b) many UPR students already take “gap” years to prepare for graduate school, but are pressured into and distracted by part-time employment for financial reasons. We will recruit students from UPR campuses in Rίo Piedras (a populous district of San Juan), Mayagüez, Cayey, Humacao, and the Medical Sciences campus in San Juan for the RING and CFAR-PREP programs. The thir...