Brain stem evoked responses (BSERs) were obtained within the first 72 hours after hospital admission from 38 patients with closed head injuries whose Glasgow coma scale scores were 8 or less. Peak V latency differentiated patients with unfavorable outcomes (vegetative or dead) from patients with more favorable outcomes, but no features of the response could further discriminate good, moderate, and severe outcomes as assessed by the Glasgow outcome scale. These data provide further support that BSERs are generally resistant to central nervous system trauma but, when impaired, are prognostic of unfavorable outcome.