Project Abstract: Over 95,000 people will die this year in the United States from excessive alcohol use and misuse (AU/M). Although alcohol is the substance most commonly used by teens, sexual and gender minority youth (SGMY) are more likely to engage in early and excessive AU/M than heterosexual and cisgender youth, placing them at greater risk for AU/M across the life course. The persistence of these disparities over the past several decades indicates an urgent need for research identifying critical periods for prevention. Yet, there remain pressing questions regarding the onset, progression, and mutable mechanisms that contribute to SGM-related disparities in AU/M during adolescence. The objective of the proposed research is twofold. First, I aim to examine developmental trends of AU/M across groups of youth defined by sexual orientation, gender identity, and race/ethnicity. Second, I will explore how normative mechanisms of alcohol use (e.g., social norms, peer influence) coincide and coexist with SGM-specific experiences (e.g., stigma) to influence SGMY alcohol use. The project will leverage the California Healthy Kids Survey, a unique population-based data source of more than one million adolescents, and primary mixed methods data collection to complete the following research aims: (Aim 1.1) Estimate developmental trends in the prevalence of AU/M across groups defined by (1.1a) sexual orientation, gender identity and (1.1b) the intersections of these identities with race/ethnicity; (Aim 1.2) Examine the extent to which bias-based bullying and perceived harm of alcohol use attenuate differences in developmental trends of AU/M across groups defined by (1.2a) sexual orientation, gender identity and (1.2b) the intersections of these identities with race/ethnicity; and (2) Explore how SGM-specific and normative adolescent factors collectively shape AU/M among SGMY. To accomplish these goals, I require additional training in SGM-specific and developmentally typical mechanisms of AU/M disparities, and complex quantitative and mixed methods approaches to investigating SGMY’s AU/M. The training plan combines tailored mentorship from sponsors and consultants with formal coursework and training seminars to provide me with the skills, resources, and mentorship needed to reach my long-term goal of becoming an independent researcher focused on understanding and eliminating AU/M inequities among SGMY. Elucidating the interplay of normative adolescent and SGMY-specific stressors implicated in SGMY AU/M will allow me to develop future research that contributes to developmentally appropriate and culturally relevant interventions to interrupt AU/M pathways and support resiliency in SGMY.