PROJECT SUMMARY/ABSTRACT. While alcohol remains the most widely endorsed substance during adolescence, and various psychosocial risk factors have been identified, unknown are the potential origins for how disparities in alcohol related problems emerge among young adults among Hispanic/Latina/x/o populations. Applying a health disparities approach to youth alcohol use (AU) prevention research is necessary to identify high impact points of intervention during adolescence before AU related problems emerge in adulthood. Given that health disparities are attributable to compounded exposure to adversity beginning in childhood, investigating relationships between the social determinants of health (SDoH) and AU and related problems in adolescence is critical. We will consider both the risk and protective role of socio-cultural factors (e.g., discrimination vs. familism) for AU and mental health during adolescence using the ecodevelopmental framework, with a focus on Hispanic/Latina/x/o youth. Further, understanding SDoH (e.g., school and neighborhood features) associations with AU and related problems will guide policy to identify upstream determinants that can be intervention targets to bring systemic change that reduces health disparities. This proposal will leverage the Adolescent Brain Cognitive Development® (ABCD) Study, a large comprehensive dataset, to advance critical areas of research in AU prevention with a focus on Hispanic/Latina/x/o youth and intersecting identities (e.g., gender and generational status). A quantitative analysis will test (1) socio-cultural determinants of AU related problems and mental health, and (2) AU influences on mental (anxiety/depression) in association with cognitive and school performance in Hispanic/Latina/x/o youth. This proposal will use ABCD study longitudinal data to identify promotive socio-cultural factors (i.e., high familism and low discrimination) that may buffer risk for AU and related problems influenced by both risk from individual and broader social- cultural contexts (i.e., school and neighborhood). Potential co-emerging disparities in mental health among youth will be investigated, and whether mental health (i.e., anxiety/depression) outcomes moderate (i.e., exacerbates) the influence of AU on adolescent cognitive functioning. This proposal will then extend the application of the SDoH framework with community-engaged research approach to conduct a qualitative study with focus groups with Hispanic/Latina/x/o youth and parents and obtain a response to the ABCD study quantitative findings to identify research gaps and priorities for AU related problems in the Hispanic/Latina/x/o community. Findings will inform hypotheses on future AU prevention research using community-engaged approaches with Hispanic/Latina/x/o youth in a future R01. In summary, the quantitative and qualitative studies proposed will investigate the socio-cultural determinants of potential co-emerging disparities in alcohol use and men...