ABSTRACT – POLICY IMPACT CORE The Policy Impact Core supports the CHIPTS mission by promoting policy-relevant research, training, and dissemination activities that address mental health and substance use disorders, social and structural determinants of health (hereafter “comorbidities”), and health disparities among people living with or at elevated risk for HIV. The core aims to leverage policy to address issues and to translate scientific advances into actionable policy items; activities that impact the gaps between targets and outcomes that can be attributed to systemic inequities linked with comorbidities. The core uses data and scientific findings to highlight systemic disparities in HIV prevention and treatment outcomes across racial/ethnic, sexual orientation, gender, and mental health/substance use disorder groups that are overrepresented among socioeconomically disadvantaged populations. Focusing on populations made vulnerable by changes to health policy, experiences that lead to medical mistrust and over engagement with the criminal justice system, the core contributes to CHIPTS research themes and stewards policy-level change in response to new developments in science, policy, and practice towards equitable ends. Through elevating community-informed research addressing factors that negatively and disproportionately affect Black, Latinx, and Native American populations with comorbidities, the core supports efforts to use policy to increase access and equitable opportunities for combination HIV prevention and treatment. These points illustrate the unique perspective and focus the core brings to the overall center. The specific aims are: (1) Science: To promote and evaluate policy change in response to scientific research that addresses barriers and facilitators to equitable dissemination and implementation of emerging innovations, especially regarding HIV-related disparities and people with or at risk for HIV with comorbidities and/or criminal justice system involvement; (2) Networking: To develop, strengthen, and maintain channels of communication with policy makers, community stakeholders, investigators, and state and local public health entities; and (3) Capacity Building: To build the capacity of investigators, including domestic and international partners, to implement and evaluate evidence-based policies that aim to increase contributions of emerging innovations to end the HIV epidemic. The core works to promote policy-relevant research, training, and dissemination that address mental health and substance use disorders, social and structural determinants of health, and health disparities among people living with or at high risk for HIV. The gap between targets and outcomes can be attributed to systemic inequities in social determinants of health.