Participants were 2,447 students in 94 classes in 31 schools that were operating drug prevention programs. The schools were divided into two groups according to the model they used in their programs. Fifteen schools used a peer-led model, and 16 used the adult-led model. A 46-item questionnaire was constructed for the purpose of examining the students' perceptions of the programs. The survey findings show that all the input measures (content, atmosphere, openness, discipline, and facilitators' competence) and the outcome measures (satisfaction, knowledge, avoidance, curiosity, and personal relationship) were perceived by the students as more positive in the peer-led model. The differences in perceptions between the two models were small but significant. Although the findings suggest that the peer-led model has a somewhat greater potential for primary prevention, the differences were not great enough for the researchers to conclude that the peer-led model was preferable to the adult-led model for primary prevention purposes. 3 tables and 23 references