Since the recognition of HIV as the cause of AIDS, considerable resources—both human and economic—have been allocated to the development and evaluation of efficacious interventions to halt the transmission of the virus and the progression of the disease. For an even longer period, researchers have worked to develop and evaluate efficacious interventions to prevent the transmission of other sexually transmitted pathogens and to treat and cure the diseases caused by them. The interventions studied have included behavioural interventions, treatments, vaccines, vaginal microbicides and male circumcision. A recent review of trials of interventions to prevent sexual transmission of all sexually transmitted infections (STI) including HIV identified 83 trials of individual, group or community-level interventions and concluded that, although many interventions have been found to be effective against STI including HIV, few have been replicated, widely implemented or carefully evaluated for effectiveness in other settings.2