We report 12 children with severe obesity in very early childhood who had no evidence of organic causes for their obesity and whose families evidenced psychosocial dysfunction comparable to that often seen in growth failure of psychosocial origin. Features seen include family disorganization, separation of mother and child, displacement of child care to others, maternal depression, denial of the growth abnormality, hostility towards health care providers, and inconsistent medical follow-up. In all cases, parental limit setting was impaired. We suggest that this condition should be called "severe obesity of psychosocial origin." Very severe obesity of early childhood may be conceptualized as the mirror image of growth failure. Like growth failure, it requires evaluation and management focused on psychosocial issues. Research is needed to clarify the prevalence, diagnostic features, and optimal treatment of obesity of psychosocial origin.