This paper reviews recent literature on male bisexuality and HIV risk and suggests new directions for intervention and research in the United States. AIDS case reports and behavioral studies based on convenience samples suggest that behaviorally bisexual men use condoms inconsistently with male and female partners, seldom disclose their bisexuality to their female partners, and are more likely than exclusively homosexual men to report multiple HIV risk behaviors. Male bisexuality may present greatest HIV risk in the context of (a) male prostitution, (b) injecting drug use, (c) sexual identity exploration, and (d) culturally specific gender roles and norms such as those that may characterize some African American and Hispanic communities in the United States. We review individual and community level interventions to reach men within these four contexts as well as the larger population of bisexual men. We also suggest a heuristic model to encourage additional research examining multiple dimensions of bisexual behavior and HIV risk.