This pilot study evaluates the effects of a peer developed, smoking prevention program on the smoking behavior, intent to smoke, knowledge, and attitudes toward smoking of high school students. An experimental group of 237 first and second grade high school students (mean ages 12.2 and 13.2 respectively) from an Athenian school was compared to a control group of ninety students from the first and second high school grades (mean ages 12.1 and 13.3 respectively) in another school. A randomly drawn subgroup of thirty-seven student volunteers from the experimental group developed antismoking audiovisual material which they subsequently presented and discussed with the whole group. Findings indicated that this intervention significantly limited the increase of smoking behavior of the experimental group a year following the first assessment. However, intent to smoke in the future, attitudes toward smoking, and knowledge were not affected by the intervention. Results suggest that the intervention was partially successful in curbing experimental smoking in these adolescents. Implications of the findings are discussed.