During adolescence girls become increasingly preoccupied with unrealistic ideals about body weight, often leading to dieting and unhealthy compensatory behaviours. Restrictive weight control practices have been linked to psychological, social, and health consequences, resulting in interest in eating disorder prevention initiatives. Participatory interventions offer promise in addressing risk factors for disordered eating. Peer-support groups in particular have demonstrated effectiveness when implemented prior to more comprehensive programming, though little is known about their effectiveness as a solitary intervention. Using a repeated measures design, this study explored the effects of peersupport on measures of body satisfaction, weight loss/weight gain behaviour, internalization of media ideals, weight based teasing, and communication, for a cohort of grade 8 girls. While the intervention did not demonstrate any effect for the group overall, high-risk participants demonstrated trends toward decreased internalization of media ideals, and increased body satisfaction. Implications and future research direction are discussed. 1 ACKNOWLEDGEMENTS Reflecting on both the time spent developing, researching, and writing this work, as well as the coursework that preceded it; I am struck by the multitude of ways in which I have been supported. This acknowledgement is only a small indication of the enormous gratitude that I feel. Unfortunately, it inevitably fails to account for the full range of individuals who contributed to my success in this endeavour. Foremost, I would like to thank Reana Saraceni, Jackie Dahien, and the students who took part in the peer-support program. Without your contributions this work would not have been possible. I would also like to express my gratitude to my supervisor, Dr.Shelly Russell-Mayhew, who guided me and lent me her confidence in this work. Shelly, your support has been instrumental in my academic and professional growth and my appreciation is immeasurable. Gisela Engels and Dr. Walter Zwirner also made significant contributions to this research through their input into the statistical analysis.To Dr. Zwimer in particular, I count myself lucky to have had you as an instructor before your retirement. I would also like to voice my appreciation to Dr. Sharon Cairns and Dr.Jenny Godley for being part of my examination committee. To Sharon, I've valued your tremendous support over the years and look forward to your continued mentorship.As ever, I thank my family members for their love, support and encouragement throughout this process. Finally, I would like to thank my partner, Gavin, the only person in the world who is likely to experience relief commensurate to mine at the conclusion of this process.