The present study was designed as an outcome analysis of a residential summer weight-loss camp with the goal of identifying positive psychological characteristics salient to the treatment and ultimately prevention of overweight and obesity in children and adolescents. Attendees (n=63) between the ages of 9 and 17 participated in a 4- or 8-week intervention program that included increased physical activity, nutritional education, and immersion in an emotionally supportive atmosphere. Outcomes were measured in terms of improved optimism, exercise self-efficacy, health-related quality of life, self-esteem and weight loss and were examined in conjunction with a comparison group (n=28). Results indicated that camp participants significantly improved levels of self-esteem and health-related quality of life over the course of treatment, had levels similar to normative samples by the end of camp, and that extended participation in camp did not necessarily yield greater improvement in psychosocial outcomes.