The timing of surgery in patients suffering from subarachnoid hemorrhage grade IV and V according to Hunt and Hess, is still controversial. Several authors advocate early surgery for patients in poor clinical condition. Improved outcome and decreased mortality rates were reported. Others exclude patients in poor condition from early aneurysm surgery. Forty grade IV aneurysm patients were admitted to our department. After ventriculostomy and cerebral angiography, 28 of them were operated on within 72 hours. The postoperative treatment included hypertensive, hypervolemic, hemodilutional therapy (triple-H therapy) and intensive monitoring (intracerebral pressure, blood pressure, hemodynamic parameters). The mean follow-up time was 6 months. Out of the 28 patients who underwent early surgery, 64% were in good health, 11% in poor health, 25% died; there were no survivors in a vegetative state. Twelve patients were treated conservatively; 50% died from infarction and rebleeding, before the operation was performed. Six underwent delayed aneurysm surgery after clinical improvement. In this group, 25% had good clinical outcome. Our results favor an aggressive treatment of grade IV aneurysm patients by means of ventricular drainage, early surgery and triple-H therapy.