A detailed review, based on the literature and the author's own series, is given of the incidence of both early and late epilepsy following head injury related to age, severity and other specific features of the injury and clinical sequelae. Use of prophylactic anti-convulsant therapy, following head injury, remains controversial despite positive results of animal experiments. Hence, the author recommends that antiepileptic medication should be restricted to patients who have had at least two epileptic fits during the first two years after injury.