This study uses a modeling approach to estimate the effectiveness of HIV prevention interventions for criminal justice involved black men who have sex with men (BMSM). Because of frequently transient life circumstances, disruption of social and sexual networks, and HIV transmission overlap with other risk groups, criminal justice involved (CJI) BMSM represent an important intervention target. Research to determine intervention impact at these larger social units does not readily lend itself to study via the randomized control trial approach. Utilizing local and national data sources, we will parameterize an Agent Based Model to assess the interplay between social and behavioral factors and viral and host factors adaptive to temporal, network and setting-specific changes on HIV transmission dynamics. The study also involves collecting new data on network shocks and HIV service utilization during critical transition periods of BMSM from the community, to jail, and back to the community/supervision, which will be used to inform model parameters. For more information, please contact Victoria Buckman.