To determine the potential benefits of a residential summer camp to treat childhood obesity, 21 obese, multiethnic children (aged 11.4+/-1.4 years; body mass index [BMI] percentile 98.5+/-1.4; BMI z score 2.30+/-0.33) from a diverse socioeconomic background were enrolled in a 2-week summer camp program. Significant improvements (P<0.04) were observed in self-esteem (+0.27+/-0.33 point), body weight (-3.7+/-1.2 kg), BMI (-1.60+/-0.48 kg/m), BMI z score (-0.12+/-0.06), number of curl ups (+10.9+/-21.5), systolic and diastolic blood pressure (-10.8+/-13.4 and -9.4+/-5.5 mmHg, respectively), and heart rate (-8.2+/-12.7 bpm).