The Community Intervention Trial for Youth (CITY) study is a 13-community randomized control trial designed to evaluate a multi-component, community-level intervention for MSM ages 15-25 (i.e., young MSM or YMSM). All 13 communities have some form of HIV-prevention activities naturally occurring in their jurisdiction, but 6 of the 13 communities were randomly assigned to also receive the multi-component intervention (1 additional city served as a case study and also received the intervention). This intervention includes 4 components: 1) community health advisor network (CHAN) consisting of YMSM who conduct outreach to their peers, including linking other YMSM to community services and conducting other parts of the intervention; 2) social marketing, to include the use media to disseminate HIV risk-reduction messages and promote positive norms for safer sex; 3) large group events with an HIV prevention theme; and 4) small group activities/workshops that focus on increasing HIV prevention skills and enhancing a positive self-identity.