As the HIV epidemic moves into its fourth decade, it is clear that the global response has failed to adequately address the needs of a wide range of vulnerable populations and groups. Chief among these are gay, bisexual and other men who have sex with men, and transgender persons, who globally face the disproportional burden of HIV infection. This volume rethinks HIV prevention and health promotion for sexual and gender minorities – in both the industrialised societies of the West, as well as in the developing nations of the Global South. The chapters it contains offer a critical analysis of past and present HIV research employing categories to designate gay and other men who have sex with men, transgender persons, and/or other persons and communities with diverse gender and sexual identities. Contributors question the politics of many of the existing classifications and categories in HIV research and argue for a more sophisticated analysis of gender and sexual diversity in order to tackle the social and political barriers that impede the design of successful HIV prevention and health promotion approaches. This book was originally published as a special issue of Global Public Health.