Fifty-eight children with syncope were evaluated prospectively to determine the characteristics of syncope in the pediatric age group and the yield of various diagnostic tests. The age at first syncope ranged from 0.5 to 15 years. Twenty-five children presented after a single episode and 33 after multiple episodes. Ten had a history of breath-holding spells. Nineteen had a family history of syncope. A diagnosis was established in 53 patients (91%): vasodepressor (31), cardioinhibitory (13), tussive (3), hyperventilation (2), and mixed syncope (4). In five patients (9%), the cause remained unknown. The diagnosis was established from the history in 45 cases, by a positive oculocardiac reflex in 11, and by the head-up tilt test in four. We conclude that the cause of most cases of pediatric syncope is vasodepressor or cardioinhibitory and can be diagnosed by good history-taking. Costly evaluations are rarely necessary.