Project Summary The early onset of tobacco use among Latinx adolescents in the United States is a growing public health concern as it increases adolescents’ risk of developing a dependency on tobacco products and related chronic health diseases in adulthood. The expected growth and prevalence of substance use in the Mexican-origin population underscores the importance of improving our understanding of the familial and cultural factors that may prevent the early onset of tobacco use among Latinx adolescents. Some well-established cultural factors of relevance to substance use prevention and intervention efforts among the Latinx community include adherence to Latinx cultural values such as familismo (the value of family loyalty) and respeto (respect for authority figures). However, literature has largely ignored the role of Latinx caregiver-adolescent dynamics (e.g., caregiver-youth cultural value differences, family conflict, and parental monitoring) on aggravating adolescent tobacco use. Thus, the present study takes a culturally-sensitive approach to understanding Latinx adolescent tobacco use and its influences via consideration of the system-level influences of family, culture, and their interactions over time. This project’s overarching goal will be achieved via three specific aims: (1) examine the association between cultural values and adolescent tobacco use over time; (2) examine the association between parental monitoring, family conflict, and adolescent tobacco use over time; and (3) examine the relation between caregiver-adolescent cultural value discrepancies, family conflict, and adolescent tobacco use over time using a mixed methods approach. The aims will be addressed by leveraging data collected as part of the California Families Project (CFP), an ongoing longitudinal study of 674 Mexican-origin caregiver-adolescent dyads from the Sacramento and Woodland, CA, school districts. CFP survey measures include questions regarding caregiver- and adolescent-reported cultural values (i.e., familismo and respeto), parental monitoring practices, family conflict, and tobacco use. The second phase of the proposed mixed methods study will involve four focus groups (two caregiver and two youth groups) of six participants each (N = 24) from the Richmond and Greater Richmond, VA, area and will explore perceived cultural value differences, other tobacco use influences, family communication about tobacco use, and ATP use. Findings from this study will contribute to NIDA’s goal of identifying and developing approaches to reduce health disparities by elucidating the ecological factors that promote or impede prevention, treatment and recovery of substance use among Latinxs. Moreover, the research and training outlined in this NRSA F31 predoctoral fellowship application will equip me with the skills and mentoring needed to pursue a career as an independent researcher, including knowledge of substance use research, advanced statistical methods, the respo...