We present a patient with gelastic seizures, precocious puberty and a hypothalamic hamartoma. The diagnostic method of choice for hypothalamic hamartoma is new generation MRI. The characteristic MRI images along with lack of growth during the course of disease indicates a diagnosis of hamartoma firmly with no need for pathological studies. Although the physical nature of gelastic seizures in this syndrome is a subject of dispute, SPECT findings point to activity at a distance from nerve routes connecting the hypothalamus to the cortical regions (the temporal region in this case). Prognosis improves if the various components of the syndrome are treated early and when dysgenesis is less extensive.