The objective of this study was to examine the social mixing and sexual risk taking of African-American men who have sex with men (AAMSM). The design was a cross-sectional survey with targeted, ethnographically informed recruitment of respondents (n = 95), and subsequent recruitment of their network partners (n = 63). We ascertained current demographics, occupation, peer norms for sexual activity, community involvement, and information about members of their social and sexual network. Risk level was categorized by the frequency of anal sex and the consistency of condom use for anal sex. Twenty-nine of 158 (18.4%) persons were classified as being at high risk (any anal intercourse in the past three months with less than 100% condom use); 79 of 158 (50%) were at medium risk (any anal intercourse in the past three months with 100% condom use reported), and 50 (31.7%) were at low risk (no reported anal intercourse). The risk groups were similar with regard to perception of behavioural and community norms. White-collar workers associated predominantly with each other and other groups mixing preferentially with white-collar workers. Clustering within contact networks (the extent to which partners to a respondent know each other) was high for all risk groups (approximately 0.4-0.5), indicating dense, interactive networks. In conclusion, this study group demonstrates a greater degree of social mixing and heterogeneity than is commonly assumed for AAMSM. At least some portion of AAMSM has internalized public health messages about safer sexual activity. Intervention programmes should avoid the pitfalls of assumed homogeneity.