Approximately 2418 total participants will be enrolled into the study at six different sites. Participants will be enrolled in one of two ways: either directly from the community, or referred by other participants (sexual network partners). The total duration of the study will be two years. This includes 12 months for participant accrual and 12 months of follow-up for each participant. All participants will have an enrollment visit, during which he will complete a questionnaire covering topics such as sexual risk behaviors, drug and/or alcohol use, current and prior engagement with the health care system, barriers to HIV care, unmet service needs, frequented venues, attitudes about race, sexual history, research, and health care. Participants will also be asked to enumerate 5 social and 10 sexual network members (age, race, HIV status), information which will be used to better understand the characteristics of black MSM social and sexual networks.