ABSTRACT The goal of this diversity supplement is to leverage global positioning systems (GPS) spatial mobility data to guide in-depth qualitative interviews examining the antecedents and consequences of intersectional minority stress in HIV-negative Black and Latinx sexual minority men (SMM) who use stimulants. Black and Latinx SMM experience profound HIV-related health disparities that are amplified by co-occurring use of stimulants. In 2018, 47% of all new US HIV infections were among Black and Latinx SMM. Overlapping structural factors such as racism, heterosexism, incarceration, and urban migration patterns within the built environment are important drivers of these racial disparities. Use of GPS tracking to analyze spatial mobility will allow us to use objective location data paired with narratives from participants explaining how interactions within certain spaces lead to stigmatizing experiences, and how those impact substance use behaviors. We can use this paired, mixed method approaches to place to the exposure before the outcomes, i.e., the environmental movements before the intersectional stigma and consequential substance use. This is a novel application of GPS methods to advance our understanding of intersectional stigma. To our knowledge, no previous studies have used GPS data to understand the impact of spatial mobility on the relationships among intersectional stigma, stimulant use, and HIV risk. We will Enroll 30 HIV-negative Black and Latinx sexual minority men living in South Florida who use stimulants as part of parent R01. Implement a mixed-methods design, first collecting GPS data from participants to plot their geographic mobility within the different areas of interests, including work, home, social and sexual activity spaces over a two-week span. A following qualitative component would leverage the mobility maps to guide an in-depth qualitative interview to understand how their dynamic movements related to experiences of intersectional stigma vary across settings, and what (if any) implications this has for their substance use. Mentoring and Training: The proposed diversity supplement training plan is sponsored by Dr. Adam Carrico and co-sponsored by Drs. Dustin Duncan and Audrey Harkness. Training includes advanced methods in GPS spatial mobility data collection and analysis, geographic information systems (GIS) computation methodology, design and implementation of intersectional stigma qualitative research, psychopathology, social psychology, and cognitive neuroscience relevant to addiction, and HIV prevention, care and treatment science. This diversity supplement will provide an ideal foundation for a planned F32 application where I will build upon this work to integrate ecological momentary assessment (EMA) methods with GPS data collection to understand how the experiences of intersectional stigma that fuel stimulant use and HIV risk vary across environmental contexts.