Modern microsurgical techniques enable most survivors of subarachnoid haemorrhage following ruptured intracranial aneurysm to make a good functional recovery. Nevertheless, it has been suggested that such patients suffer from a persistent disturbance of cognitive function. When tested 6 weeks after their discharge from the neurosurgical unit, patients from a consecutive series of 76 cases of aneurysmal subarachnoid haemorrhage demonstrated a moderate impairment of performance across a broad range of cognitive tasks. This was more pronounced in the case of patients who had suffered generalized postoperative vasospasm, but was unrelated to the site of the ruptured aneurysm. However, when patients were tested 6 months after discharge, the only consistent deficits were in the speed of retrieval of verbal items from semantic memory, and there was little evidence of any generalized cognitive impairment.