PROJECT SUMMARY/ABSTRACT Background: Male sex workers (MSWs), or men who exchange sex for money, goods, drugs, or other items of value with other men, are at exceptionally high risk for HIV infection. Pre-exposure prophylaxis (PrEP) is effective at reducing HIV acquisition among HIV uninfected individuals, but its efficacy is highly dependent on uptake and excellent adherence. However, uptake of and adherence to PrEP among those who might benefit the most from using PrEP, such as MSWs, remains suboptimal. A successful PrEP uptake and adherence package must be responsive and tailored to MSWs’ distinct psychosocial and contextual circumstances. Overview of Proposal: The current proposal is a culmination of over 10 years of research with this population, including qualitative research, epidemiological assessments and programmatic work. These formative data led to an NIMH-funded R34 (MPIs: Biello, Mimiaga, Chan), which allowed our interdisciplinary team and community partners to collaborate on the development and pilot testing of a theory-based intervention— “PrEPare for Work”—to address 1) access to and uptake of PrEP at local PrEP clinics/providers via strength- based case management using principles of motivational interviewing (e.g., focusing on values, strengths and change efforts, making reflective and empathetic statements), and 2) provide cognitive-behavioral therapy- informed PrEP adherence counseling (e.g., problem-solving skill-building) with personalized, daily text message reminders to optimize PrEP adherence among MSWs. The pilot RCT demonstrated the feasibility, acceptability and preliminary efficacy of “PrEPare for Work”. Conceptual Model: The “PrEPare for Work” intervention is based on Social Cognitive Therapy (SCT), which specifies a core set of mechanisms that influence health behavior with a primary emphasis on self-regulation and self-reflection, including self-efficacy. Overview of Study Design: We now propose to test the efficacy of the “PrEPare for Work” package in the Greater Providence area and in Los Angeles County using a two-stage randomization design. Stage 1: 500 MSW will be equally randomized to receive either the “PrEPare for Work Stage 1 intervention” (strength-based case management and facilitated PrEP linkage) or standard of care to evaluate successful PrEP uptake (verified by real-time tenofovir urinalysis; prescription data) within 2 months. Stage 2: those who initiate PrEP (n~156; ~55% from Stage 1 intervention arm and ~20% from Stage 1 SOC arm) will be equally re-randomized to the “PrEPare for Work Stage 2 intervention” (1-on-1 skills training, problem solving, and motivational interviewing adherence counseling and personalized, daily text messaging reminders) or SOC to assess PrEP adherence (tenofovir concentration in hair sample) and retention in PrEP care (appointments attended) over 12 months. We will also examine the degree to which improvements in PrEP uptake and adherence occur in the context of the conc...