PROJECT SUMMARY Adolescents growing up in urban neighborhoods with high rates of poverty and violence experience high rates of community violence. Minority youth are more likely to reside in neighborhoods with high rates of poverty and violence and consequently report higher rates of exposure than their White peers. Early adolescents are particularly vulnerable to consequences of community violence because they are increasingly susceptible to environmental, biological, cognitive, and emotional processes that increase their risk of psychopathology. Witnessing community violence has been associated with both internalizing and externalizing symptoms. However, findings of relations between witnessing community violence and internalizing symptoms have been inconsistent, and theories offer contradictory predictions. There is a gap in our understanding of the effects of witnessing community violence on adolescent development, which may reflect limitations of prior studies. The goal of the proposed study is to address those limitations by identifying trajectories of witnessing community violence across early adolescence, investigating the extent to which subgroups differ in their trajectories, and determining the extent to which trajectories of witnessing violence are related to changes in physical aggression and distress symptoms. This goal aligns with NICHD's research priority of understanding the impact of adverse experiences during childhood and adolescence on development and identifying periods where intervention could have optimal effects. These aims will be addressed through analysis of a unique and rich dataset with 12 waves of data that were collected every three months across all three grades of middle school from a predominantly African American sample of 2,755 early adolescents living in urban communities with high rates of violence. Latent curve models, growth mixture modeling, and latent profile analysis will be used to examine within-person changes over time and between-group differences in within-person change. The specific aims are to: 1) identify within-person changes in witnessing community violence during early adolescence, 2) investigate longitudinal relations between witnessing community violence and physical aggression and distress. Sex differences will be examined for each aim. Refinement of theories related to chronic exposure could inform intervention and prevention efforts to promote positive youth development. Identification of subgroups with different patterns over time could be used to tailor interventions, and could highlight periods where interventions might be most effective. Moreover, the research and training outlined in this NRSA F31 pre-doctoral fellowship application will equip me with the skills and support needed to pursue a successful career as an independent research scientist by providing me with knowledge of relevant theoretical models and their application to prevention efforts, competencies in advanced stati...