My research program focuses on effective community-based HIV prevention services and access to HIV care. My work emphasizes the needs and experiences of adolescent and young adult Black sexual minority males in the United States, Africa, and the Caribbean. I am interested in identifying structural and community-level HIV prevention programs that are effective in reducing HIV-related risk behavior among high-risk young sexual minority men and in facilitating their timely access to affirming sexual health care and HIV treatment. I am particularly interested in how racial and homophobic structural stigma processes restrict young gay and bisexual males' access to HIV-related services and identifying interventions to reduce structural stigma. My work also focuses on the contextual conditions in AIDS-related community-based organizational environments that contribute to sustainable HIV prevention, HIV testing, and linkage-to-care activities. My work on community-based and civil society organizations draws heavily from program evaluation and implementation science perspectives. My research is grounded in the idea that a program and its environmental host combine to make a causal package; one cannot understand what makes a program effective and consider where and for whom else it might be effective without treating the program's context as part of the program. In addition, I am a scholar of evaluation theory and practice, with particular interests in the relationship between evaluation theory and practice and the history of contemporary evaluation theory.