Long-term recovery from severe closed head injury was investigated in predominantly young adults whose Glasgow Coma score was 8 or less at the time of admission. Of the 27 patients studied (median follow-up interval of 1 year), 10 attained a good recovery, 12 were moderately disabled, and five were severely disabled. In contrast to previous studies suggesting that intellectual ability after severe closed head injury eventually recovers to a normal level, our findings showed that residual intellectual level, memory storage and retrieval, linguistic deficit, and personal social adjustment corresponded to overall outcome. All severely disabled patients and several moderately disabled patients exhibited unequivocal cognitive and emotional sequelae after long follow-up intervals. Analysis of persistent neuropsychological deficit in relation to neurological indices of acute injury severity demonstrated the prognostic significance of oculovestibular deficit.