Renewed uncertainty regarding the best technique of surgical therapy (burr holes versus craniotomy) for subdural empyema prompted a review of the experience with this disease entity at UCLA. Based on data obtained from this review and from studies previously published in the literature, the keys to optimal outcome are rapid diagnosis, craniotomy with total removal of pus, and appropriate antibiotic therapy. The clinical syndrome of subdural empyema can overlap that of other intracranial infections; infants and young children present with a different syndrome than older children and adults. Computed tomography scanning is nearly always diagnostic but may be equivocal or normal; magnetic resonance imaging may become the diagnostic study of choice. Multiple organisms are often cultured, which requires multiple drug therapy.