A consecutive series of 93 severe closed-head injury (SCHI) patients, discharged from hospital in a conscious state, were rated on the Glasgow Outcome Scale at 6 and 12 months post-injury. Patients were included in this study if they had a period of post-traumatic amnesia (PTA) exceeding 24 h. Approximately 80% of patients had made a good recovery by 12 months post-injury; a better outcome than has been found in studies using the presence of coma during the first 6 h post-admission to hospital to define severe head injury. When analysed individually, duration of PTA and Glasgow Coma Scale scores on admission to hospital were both strongly correlated with outcome. Only duration of PTA, however, contributed significantly to outcome variance when potential outcome predictors were assessed using a stepwise multiple regression analysis. The definition of severe head injury, the higher than usual incidence of good recovery in the present study, and the relationship between injury severity and outcome are discussed.