A school-based program aimed at the primary prevention of eating disturbances was developed, implemented, and evaluated. The eating disturbances targeted included unhealthy dieting and binge-eating, which are common among nonclinical populations of adolescent girls. The program was based on social-cognitive principles for behavioral change, and the goals were to change knowledge, attitudes, and behaviors related to nutrition and weight control; improve body and self-image; and promote greater self-efficacy in dealing with social pressures regarding excessive eating and dieting. The baseline population included 341 tenth-grade girls from 16 classes at three high schools in Jerusalem. Classes were assigned to intervention or control groups and girls in the former participated in a 10-session program. Program effectiveness was evaluated with a quasi-experimental design for 269 girls who were present at follow-up assessments conducted both 6 months and 2 years after program implementation. Results indicated that the program had moderate effects on nutrition knowledge and meal patterns and on preventing the. onset of unhealthy dieting and bingeing behaviors. The effects were most consistent among overweight girls. The results suggest that school-based programs can contribute to primary prevention of eating disturbances.