My research has consistently focused on the effects of poverty and of social/cultural context on the health of our most disadvantaged youth, particularly homeless youth in San Francisco and street children in Kisumu, Kenya. Through my work in San Francisco since 2001, I demonstrated the feasibility of longitudinal epidemiological work with street youth, demonstrated the role of street culture, social networks and race in HIV risk of street youth, and developed a community collaborative project for street-based STI testing of street youth. Since 2007, I have been engaged in translating my work to the Kisumu context. The Vijana Wetu (Our Youth) Project demonstrated the feasibility of ethnographic research with Kisumu street children. Furthermore the project demonstrated the feasibility of the use of a novel approach to sampling hard-to-reach populations, Respondent Driven Sampling (RDS), for the recruitment of street children for a longitudinal study of HIV/STI risk. The next step for my research is to develop skills in community-engaged research for the development of structural interventions that address the social and cultural determinants of youth's HIV risk. The proposed mini-sabbatical would allow me intensively focus on two closely-related goals to develop my skills in community-engaged research. The first goal would be to develop a community-engaged pilot proposal for the surveillance of street-based and unstably housed youth in San Francisco that could be used as a model for such surveillance elsewhere. The second goal would be to conduct a community consultation with stakeholders in Nyanza to assess the feasibility of community-level interventions for street children and to inform the choice of structural interventions for street children. The opportunity to re-focus my work domestically and internationally on community-engaged structural interventions for youth health will greatly increase my effectiveness as a translational researcher focused on the health of these stigmatized populations of youth.