The goal of the present study was to evaluate the effectiveness of a school-based peer support group designed to improve body esteem and global self-esteem and to reduce negative eating attitudes and behaviors. A total of 214 girls in grades 7 and 8, 115 of whom were in the control group, completed self-report questionnaires immediately before and following the intervention, and three months later. The findings revealed that participation in the 10-session group, facilitated by public health nurses, led to increases in weight-related esteem and decreases in dieting. The role of peer support groups in the prevention of disordered eating is discussed.