This article reviews the recent evolution of the HIV/AIDS epidemic in Brazil and its frameworks for prevention. Considering a decade of preventions initiatives targeting young people and their educators in São Paulo, describes the surpassing of the "risk group" notions and indicators of the successes of the national efforts facing the challenges of a growing epidemic among young people. A preliminary work developed in public elementary night schools inspired several programs that have created parameters for prevention actions, indicators of the youth social context and vulnerability, described socio-cultural categories that frame daily life and sexual activities of young people. Beginning with interactive actions that focus on sex and reproduction, gender relations and other issues, various projects deal with unawareness, emotions, structural violence, and citizenship. Cooperation and acceptance was found in high degree among the various groups living in vulnerable contexts and among adults involved with them: students, incarcerated kids and young people gathered in different communities and activities.
Acquired Immune Deficiency Syndrome; Prevention; Youth; Social vulnerability