Acknowledgements Validity and Dimensions of Norms Acknowledgements

University of California San Francisco for contributions to statistical and data analyses, and to Gail Bolan and the NACS Advisory Panel for contributions to the main project. Portions of this work were presented previously at the Society for Research on Adolescence Biennial Meeting, San Francisco, 2006. We thank Marcia Macomber for assistance in manuscript preparation. 1 Validity and Dimensions of Norms Urban African American youth are at high risk for STIs (e.g., Ellen et al., 2005; Valleroy, MacKellar, Karon, Janssen, & Hayman, 1998) and are more likely to be represented among adolescent HIV/AIDS cases (Centers for Disease Control and Prevention, 2012). To date, the impact of HIV/STI public health programs in these communities has been modest. A potential weakness of past programs and the theories that underlie them is a lack of conceptual work on the complexities of social norms within the context of social development and community social structure