INTRODUCTION Obesity has become a significant national issue with pediatric obesity rates nearly quadrupled between 1990 and 2000. Although obesity affects all cultures and ethnic groups, the disorder seems to affect African Americans and Hispanics at a disproportionate rate. Obesity rates in New York City elementary public school children show that children have been significantly affected by the obesity epidemic. PURPOSE The purpose of the Downstart Pediatric Weight Loss Program is to provide a comprehensive intervention program assisting patients and families with weight loss, leading to a healthier, more active lifestyle. METHODS The Downstart Program uses a four-pronged approach of medical evaluation and a 12-week intervention of exercise, nutritional education and lifestyle modification. The medical evaluation consists of pulmonary function tests and referral to endocrinology, cardiology, orthopedics, and psychology services as needed. Baseline fitness was measured with 2 min. step test, amount of push ups, sit ups and squats performed in 30sec. The gradual, prescriptionbased exercise sessions are held twice-weekly, for an hour each, composed of flexibility, cardio-vascular endurance, and strength training components. The nutrition and behavior modification consists of weekly education about food groups, portion control, goal setting, and appropriate rewards for attaining goals. RESULTS 68 children began the Downstart program, with 48 finishing. Of these, 45 lost at least one kilogram of weight. The mean decrease of BMI was 0 .9. Fitness capacities improved among high compliant children (those attending at least 75% of sessions). This improvement was seen in an average increase of 28 steps on the 2 minute step test, 10 push ups, and 5 squats per 30 seconds. Flexibility increased an average of 1.42 inches as measured with the sit and reach box. CONCLUSION The multi-disciplinary intervention program helped most of the participants who completed the program, lose weight. Improvement in fitness parameters among the high compliant group, over their less compliant cohorts, suggests program effectiveness. The less compliant children attended sporadically, often came late to sessions or dropped out of the program, suggesting lower motivation. Our preliminary results indicate that the Downstart Program may be a viable intervention for weight loss. Further study is needed to improve motivation and to assess long-term effects on health and lifestyle.