Summary After studying 14 cases of idiopathic sexual precocity, 5 in males and 9 in females, it was decided that the most comprehensive purpose would be served if complete psychological details on a single case, together with a guide to case management, were presented. The case was that of a boy 6 years old. He had the voice, appearance, physique, energy, and physical sexual maturation normally observed at adolescence. Psychologically he was like other boys of his age, except that he had superior intelligence and was well advanced in academic achievement. He talked and acted like a bright 6-year-old, and had the interests and emotional reactions typical of that age. His store of knowledge was advanced for his age, but his motor skills were not practiced enough for him to compete on equal terms in the recreations of boys aged 8 or 9 and of his own size. His psychosexual orientation and demeanor were in keeping with his chronological age, though the magnitude of libido was that of an adolescent. There has been no evidence to contradict an evaluation of the boy's psychological adjustment as thoroughly adequate. There were no signs of distorted judgment and irrational thinking; of defective ability to master life's problems; nor of control that was either too inflexible or too difficult to maintain. He appeared to be undergoing a developmental phase of learning the appropriate balance between use and release of control. He was an unself-conscious child, exuberantly living a child's life, through its various phases of learning and maturation, in an adult's body.