Project Summary/Abstract This application is to provide mentorship and career development to a promising URM as part of a diversity supplement to grant R01MH121161. The parent award seeks to understand ongoing implementation of PrEP service delivery across two large CDC/PEPFAR funded awards to TB HIV Care in South Africa, which serve the HIV prevention female sex workers and adolescent girls and young women nationally. The parent award further aims to optimize PrEP implementation strategies to enhance PrEP uptake and persistence among women, through short duration cluster randomized trials which test modifications and additions to ongoing program implementation. The proposed application, will build upon the existing study objectives and expand the scope by studying the adaptation of strategies over time, as well as the impact of these adaptations on the fidelity of implementation. These adjustments are beyond the scope of the currently funded study which assessed the impact of the introduction of implementation strategies on PrEP uptake and persistence, and is studying the relationship between new/tweaked strategies on PrEP performance outcomes. Assessing adaptation of strategies over time is new, and will help to elicit new insights into fidelity of implementation, including fidelity consistent and fidelity inconsistent adaptations, which will provide further insights into program performance over time, as well as durability of implementation and impact of implementation strategies. Training activities will focus on expanding skillsets of the candidate, an underrepresented minority from a disadvantaged background, in implementation science, qualitative research methods and causal inference, preparing the candidate for a future research career. The mentoring team has several collective years of mentorship experience, including in implementation science, quantitative and qualitative research methods, PrEP programming, clinical research and practice and infectious disease epidemiology.