Eighty-eight cases of petit mal epilepsy in children are reviewed. The clinical characteristics and differential diagnosis of petit mal are presented in detail. Aspects discussed and significant findings are as follows: Petit mal is a relatively infrequent type of epileptic manifestation (4.4%). Petit mal is rare before 2½ years of age. Twenty-three per cent of the children had attacks for over 3 years prior to their first visit suggesting the limitations of therapy. A history of seizures in parents or siblings was present in 21% of the cases. Whereas, only 10% had apparent lesions of the central nervous system, the incidence of intellectual retardation 24%, is similar to that found in our reviews of jacksonian and psychomotor epilepsy. Sixty-one per cent had non-petit mal seizures (chiefly grand mal). In 63%, these first appeared with or after the onset of petit mal. Petit mal attacks were precipitated by hyperventilation in 93% of the cases. Ninety per cent of the children had seizure formations in at least one electroencephalographic tracing. Sixty-four per cent showed spike and wave patterns; in 26%, other convulsive patterns were noted. Recommendations in therapy and results are reported. The review suggests that petit mal is not entirely benign and unaccompanied by cerebral pathologic changes with effect on mentality or personality, nor spontaneously cured at puberty. The high incidence of grand mal and other seizures in these children is emphasized and prophylactic therapy suggested.