Obesity is a common nutritional disturbance of children and affects 25% to 30% of children and adolescents. This paper examines obesity in childhood, the measurement of obesity in children, and the relationship of obesity to coronary heart disease risks and discusses weight reduction issues in children. Clinically useful definitions of obesity in children have not been established, although the body mass index, together with anthropometric measurements, may provide the practitioner with useful assessment parameters. Discussions of weight in children must acknowledge the nutritional requirements of the normally occurring growth process. Because growth (and subsequently weight) varies widely among children even of the same age, measurement, classification, and control of weight must take into account the growth process and growth requirements. Interventions in childhood obesity should be directed toward family involvement in the chosen strategy and nutritional prudence coupled with typical activity.