A series of 4992 intracranial procedures performed over an 11-year period was evaluated for the occurrence of postoperative hemorrhage. Forty patients (0.8%) experienced postoperative hemorrhage. Twenty-four hemorrhages were intracerebral (60%), 11 were epidural (28%), 3 were subdural (7.5%), and 2 were intrasellar (5.0%). Hematomas in 33 patients occurred at the operative site, and 7 occurred remote from the operative site. Intracranial tumor was the reason for operation in 56% of the patients developing a clot, and meningioma was the most common tumor associated with this complication. The use of the sitting position was not associated with an increased incidence of postoperative hemorrhage. Disturbances of coagulation and hypertension seemed to be potential precipitating factors. Postoperative hemorrhage was recognized within 12 hours of operation in 35% of the patients. An altered level of consciousness was the most frequent clinical finding, present in all patients. There was no clear relationship between the time of recognition and the final clinical outcome. Parenchymal clots carried the worst prognosis, accounting for 8 of the 11 deaths and all 7 patients with poor neurological outcome.