Relatively little research has examined the personal sex lives of indoor male sex workers (MSWs) or possible connections in this group between sexual behavior and factors related to HIV risk. As part of a larger project, this study collected data from 30 agency-based indoor MSWs (mean = 22.4 years) about their sexual behavior, mental health, and substance use. Few HIV risk behaviors with clients occurred. Drug use and mental health problems were relatively frequent, but not related to increased risk behavior. Instead, MSWs appeared to employ rational decision-making and harm-reduction strategies. Conceptualization of MSW sexual behavior may be required where HIV risk is not attributed to sex work per se, but to other influences such as economic and relational factors.