Between 1981 and 1985 at our clinic 204 consecutive patients underwent surgical repair of cerebral aneurysms after spontaneous subarachnoid hemorrhage. Of these 113 were treated with Nimodipine, a predominantly cerebrovaskular-active substance. The preoperative condition according to Hunt and Hess (9), the locations of the aneurysms, and the ages of the two groups of patients were directly comparable. The incidence of postoperative cerebral vasospasm was however higher in the Nimodipine group (49%) than in the control group (33%). Retrospectively we analyzed the progress of the patients as to their neurological, intellectual, and social function for up to five years after the operation. Mortality and morbidity in the Nimodipine group amounted to 10% and 7% respectively, in the group without Nimodipine 20% and 17% respectively (p less than 0.001). Of the Nimodipine patients, 72% showed excellent neurological outcome, with 73% intellectually, and 72% completely resocialized, as compared to 53% in the control group with an excellent neurological outcome, 39% intellectually intact (p less than 0.0001, and 52% completely resocialized (p less than 0.01). These results suggest that Nimodipine not only increases cerebral blood flow, but also protects brain tissue from ischemic damage.