The volume of neurotrauma experience and mortality after head injury were evaluated in 4667 patients admitted to 10 Level I trauma centers. The hospitals were divided into three groups based on the number of severely head-injured patients admitted each month. The mean number of patients admitted each month to Hospital Groups 1, 2, and 3 with a Glasgow Coma Scale (GCS) score > 10 was 100.0, 18.2, and 10.6. Mortality was significantly lower for patients admitted to Group 1 than for those admitted to Group 2 or 3; however, the difference between Groups 2 and 3 was not significant. The mean number of admissions with a GCS score < or = 10 was 8.3, 6.5, and 2.8, and mortality rates were 26.7 per cent, 36.5 per cent, and 41.4 per cent, respectively. Mortality for Group 1 patients was significantly lower than for those in Groups 2 or 3. Patient age also had a profound impact on survival among all hospital groups. We conclude that the volume of neurotrauma experience correlates with mortality after head injury.