In 2002 MTV launched a global multicomponent HIV prevention campaign, "Staying Alive," reaching over 166 countries worldwide. An evaluation of this campaign focused on three diverse sites: Kathmandu, Nepal; Sao Paulo, Brazil; and Dakar, Senegal. Data were collected before and after campaign implementation through population-based household surveys. Using linear regression techniques, our evaluation examined the effects of campaign exposure on interpersonal communication about HIV and the effects of campaign exposure and interpersonal communication on beliefs about HIV prevention. We found a consistent positive effect of exposure on interpersonal communication across all sites, though there were differences among sites with regard to whom the respondent talked about HIV. We also found a consistent positive effect of exposure on HIV prevention beliefs across sites when interpersonal communication was simultaneously entered into the model. Finally, in two sites we found a relationship between interpersonal communication and HIV prevention beliefs, controlling for exposure, though again, the effects differed by the type of person the communication was with. These similar findings in three diverse sites provide ecological validity of the findings that "Staying Alive" promoted interpersonal communication and influenced young people's beliefs about HIV prevention in a positive way, evidence for the potential of a global media campaign to have an impact on social norms.