PROJECT ABSTRACT People living with HIV (PLWH) experience depression at nearly two times the rate of the general population, leading to decreased quality of life,1 more rapid HIV disease progression,2 increased suicide risk,3 and increased mortality.4 In the United States, PLWH are disproportionately Black or Latinx, LGBTQ+, and living in poverty. Access to mental health services among this population is limited by myriad contextual barriers related to individual and structural factors (e.g., stigma,5 discrimination,6 poverty,7 food insecurity,8) and implementation factors (e.g., provider burnout, insufficient public funding). These challenges in accessing mental health treatment exacerbate existing inequities within this population. There is an urgent need for effective, feasible, and scalable treatment for depression in PLWH that overcomes existing access barriers. Managed Problem Solving Therapy (MAPS), a low-intensity behavioral intervention to increase medication adherence in PLWH, is an evidence-based practice endorsed by the CDC. Although MAPS was designed to specifically target medication adherence, when tested in a randomized-controlled trial, depressed PLWH receiving this treatment were twice as likely to experience depression remission compared to those receiving usual care.9,10 MAPS+, an adapted version of MAPS that focuses on medication adherence and care retention, will be delivered by community health workers (CHWs) in Philadelphia HIV clinics in an R01-funded trial (NR 019753; Momplaisir, Beidas, Gross). My proposed project builds upon the R01 project, adding a behavioral health component by 1) prospectively testing the effect of MAPS+ on depressive symptoms; 2) examining the mechanism by which MAPS+ affects depressive symptoms; 3) addressing crucial implementation questions related to mental health and health equity that are relevant to scaling up this intervention. Quantitative data will be collected from ~100 PLWH across 4 clinics over one year and will be compared to a cohort of similar patients from the same clinics from an earlier time using propensity score matching. The hypothesized mechanism of action, that MAPS+ decreases depressive symptoms by increasing self-efficacy, will be tested using mediation modeling. The proposed project also includes a qualitative aim involving multi-level stakeholders. Thirty qualitative interviews with patients, CHWs, and clinic leaders will capture perspectives on contextual barriers and facilitators to MAPS+ implementation to inform future implementation efforts in Philadelphia and beyond and to advance health equity goals. This fellowship opportunity will provide the applicant with advanced training in implementation science and statistical methods through didactics and formal mentorship. Further, carrying out the proposed research project will provide the applicant with an opportunity to develop independent research skills that will prepare her to carry out her long-term career goal of i...