Gunshot wounds to the head are associated with poor outcome. We reviewed data to identify prognostic factors. We performed a retrospective study of all patients admitted to a Level 1 trauma center with isolated gunshot injury to the head during 6 1/2 years. Data collected included demographics, mechanism of injury, prehospital and resuscitation room data, and initial CT scan characteristics. The primary outcome measure was the Glasgow Outcome Scale. Seventy-two patients with isolated gunshot wounds to the head were admitted. Overall mortality was 58 per cent. The mortality for patients with an initial Glasgow Coma Scale score of < or = 8 was 81 per cent versus 14 per cent for those with initial Glasgow Coma Scale score > 8 (P < or = 0.0001). Fifty per cent had pupillary abnormalities on arrival at the Emergency Department. Mortality in this group was 78 per cent versus 53 per cent in those with normal pupillary reflexes (P = 0.06). Elevated plasma lactate was associated with nonsurvival. Thirteen per cent of survivors were assessed as able to live independently after their injury. Civilian gunshot injury to the head is related to high mortality. Indicators of outcome are the admission Glasgow Coma Scale score, pupillary abnormality, metabolic acidosis, and CT pattern of severe injury. The majority of deaths occur at an early stage. Among survivors the functional outcome can be acceptable.