Project Summary Opioid-related overdose deaths and incarceration rates have skyrocketed and have disproportionately affected women. Despite having a higher burden of substance use disorders and HIV/AIDS than criminal justice-involved (CJI) men, CJI women are less likely to have access to substance use and HIV treatment. The proposed intervention will link and retain women with recent CJI in medication-assisted treatment (MAT) programs, identify and connect women with necessary social services, and provide women with opioid overdose response training. Specifically, the candidate aims to 1) conduct in-depth interviews with CJI women, MAT providers, and criminal justice professionals to identify facilitators and barriers to illicit opioid use cessation and decreases in HIV risk behaviors and exposure to violence among CJI women; 2) develop a gender-specific and trauma-informed intervention that utilizes peer navigation to connect CJI women with OUD to MAT programs, necessary health and social services, and provides opioid overdose response training; and 3) conduct a pilot study (randomized control trial) to assess the adequacy in which components of the gender-specific and trauma-informed intervention function together using a sample of 50 community-recruited CJI women who use opioids illicitly. In order to complete the proposed research tasks, the candidate has composed a team of internationally recognized scholars as mentors. Through this proposed K01, the candidate will expand the breadth of her work to treatment for opioid use disorders and common comorbidities. The research and training outlined in this proposal will allow the candidate to gain content expertise on social factors that lead to sub-optimal outcomes among CJI women with OUD, trauma among substance-using and CJI women, while simultaneously developing her skills in implementing and evaluating clinical trials. The candidate’s long-term career goal is to develop evidence-based interventions to reduce substance use and its co-occurring health and social consequences among marginalized and vulnerable communities. The proposed work helps her make further strides to accomplishing this goal by enabling her to design, implement, and evaluate a pilot intervention designed for CJI women.