In a follow up study of 57 patients who had sustained a severe closed head injury, 84% still reported some residual deficit in their psychological functioning after two years, with forgetfulness being the most common complaint. Expressing the severity of the injury in terms of both the duration of post-traumatic amnesia (PTA) and the extent to which previous work could be resumed (RTW), principal components analyses showed that the occurrence of "impairment complaints"--viz forgetfulness, slowness, poor concentration and inability to divide attention over two simultaneous activities--was positively related to severity. The other complaints, which in the main could be labelled as "intolerances" were not. The same pattern was found when the analyses were based on deficits of the patients as they were reported by relatives. Severity was not appreciably related to the total number of complaints. The correlation between PTA and RTW was 0.52, indicating that with longer PTA duration, work is likely to be resumed at a lower level, or not at all. Though Russell's cut-off of one week PTA to differentiate between severe and very severe concussion appeared useful, in the present study a further cut-off point at the unlucky number of 13 days was considered.