This study describes the complex dynamics of the sexual, economic and social interactions between a group of feminized homosexual men and men who have sex with men and self-identify as heterosexual ('mostaceros'), in lower-income peripheral urban areas of Lima and Trujillo, Peru. The study examined sexual risk between these two groups of men, and the significance of the economic exchanges involved in their sexual interactions. Using a Grounded Theory approach, 23 individual interviews and 7 focus groups were analyzed. The results reveal that cultural, economic and gender factors mold sexual and social relations among a group of men who have sex with men in Peru. Compensated sex is part of the behaviors of these men, reflecting a complicated construction of sexuality based on traditional conceptions of gender roles, sexual identity and masculinity. Several factors (e.g. difficulty in negotiating condom use, low self-esteem, low risk perception, alcohol and drug consumption), in the context of compensated sex, play a role in risk-taking for HIV infection. © SAGE Publications, Inc. 2008.