PROJECT SUMMARY The combined mentorship, training and research in this K01 award will support the candidate’s long term goal of formulating high impact, community-engaged HIV health disparities and social media-based research focused on sexual minority youth (SMY) of color in the South. HIV remains an insidious public health concern among Black SMY in the South. Diagnose is one of the 4 Pillars of the Ending the HIV Epidemic (EHE) Initiative and routine testing is a clear priority for this population. Infrequent or never testing for HIV has been associated with high rates of infection in Black SMY. Routine HIV testing could provide a central gateway for linkage to HIV prevention services for those at risk or early access to care for those unaware of their status; however, barriers to testing persist (e.g., internalized homophobia). Some Black SMY may be more isolated and many turn to social media. Leveraging social networks, such as through Popular Opinion Leaders (POLs), via social media can increase social support and normalize routine HIV testing. Despite its popularity, Instagram has not been utilized in HIV-focused interventions, including among Black SMY. Instagram influencers are authentic and credible social media users who are, in essence, POLs. This project proposes to enhance the EHE-recommended POL intervention promoting routine HIV testing in Black SMY in New Orleans. The project will employ 8 Black SMY Instagram influencers to implement a novel, theoretically-grounded approach to crafting persuasive HIV testing messages to their followers. To this end, the candidate will: 1) Explore HIV testing attitudes and experiences and the use of Instagram messaging to increase routine HIV testing for Black SMY in New Orleans; 2) Identify, recruit and train Black SMY Instagram influencers on HIV knowledge and social-media based messaging strategies using a novel framework for persuasive messaging; 3) Co-develop and deliver persuasive routine HIV testing Instagram messages with Black SMY Instagram influencers. A team of experienced mentors with expertise in Black SMY health disparities, HIV intervention development, persuasion theory, social media messaging and community-based participatory research (CBPR) will guide the candidate through the research. The training plan will consist of multidisciplinary didactic coursework, individualized training workshops and mentoring sessions, which will allow the candidate to: 1) Understand how multiple identities (i.e., racial, sexual) and related experiences contribute to HIV-related disparities among Black SMY; 2) Develop proficiency in persuasive social media-based health communication strategies; 3) Gain skills in the development/ adaptation, implementation and evaluation of interventions utilizing CBPR. This K01 award will give the candidate the additional skills and experience needed to achieve research independence.