This paper studies the ways in which the idea of drug abuse prevention became an issue in the fi eld of Education. It brings elements for an understanding of how a particular way of thinking about the illegal use of certain psychoactive substances was formed, and how it found in Education a good means of implementation. The object of the study is the historical records of the “Fórum de Debates Sobre o Uso e o Tráfi co de Substâncias Tóxicas ou que Causam Dependência Física ou Psíquica” (Forum on the Use and Traffi c of Toxic Substances or which Causes Physical or Psychological Dependence), an event held in the city of Porto Alegre in the 1970s, which constitutes a landmark in Brazil as it was the fi rst event of its kind. Inspired by the theories of Michel Foucault, and based on an analysis of the above-mentioned historical records, this paper investigates the relations between the emergence of drug abuse prevention in schools, and how the web of diverse powers, understood here as circulating at government level, regulates these behaviors in a way that is cost-effective and safe.