ABSTRACT Children's Hospital Los Angeles (CHLA) Children's Hospital Los Angeles (CHLA) is proposing to be the lead site for the Los Angeles Consortium. The primary aim is to collaborate with Westat as the Adolescent Trials Network (ATN) Operations and Collaborations Center (OCC) to successfully plan and implement ATN clinical research studies to meet the priority areas as outlined in SLC RFA-HD-23-020. CHLA will leverage the strength of the Connect to Protect Los Angeles (C2PLA) Coalition to lead a Research Advisory Committee of community, clinical, and academic partners to: 1. Conduct the Research Projects identified by the ATN Executive and Scientific Leadership Committees; 2. Participate in the development of trials using our community, academic, and clinical partners in conjunction with the ATN Scientific Core to meet the needs of adolescents and young adults (AYA) at- risk for or living with HIV; 3. Contribute to innovative strategies within ATN V regarding successful recruitment and enrollment of participants through established collaborations among clinics, academic universities, community-based organizations, health departments, and other partners; 4. Provide sites with local laboratory capacity and pharmacy support; and 5. Establish a leadership model with meaningful and sustained community engagement efforts to ensure that research studies reflect where AYA are accessing prevention and care services. Our proposed consortium will initially include nine partners who will bring their strength and diversity to a site consortium that will include clinical, academic, government, community, and other partnerships. We have four clinical sites that provide care to AYA living with HIV and at risk for HIV including mostly LGBTQ AYA of color and two partners that currently house large databases of AYA living with HIV and at risk for HIV: ATN CARES at UCLA and the NIDA UO1-funded Healthy Young Men/A Trans Youth of Color Study cohort at CHLA. We have initially targeted four community-based organizations and the County of Los Angeles Department of Public Health Division of HIV and STD Programs. Representatives of these groups and our AYA community advisory boards will form an innovative leadership structure that is representative of our communities and can provide leadership through protocol review, new protocol development, and guidance on recruitment and retention. Based on decades of experience with clinical services and research with AYA, our proposed Los Angeles ATN V Consortium is well suited to join the OCC and other city consortia. CHLA has exceptional access to AYA likely needed in future clinical trials, decades of ongoing community partnerships, and an outstanding track record for recruiting and retaining hard to reach AYA into clinical trials, including complex medical interventions requiring investigational new drugs (IND), research laboratories, and pharmacy services.