The incidence and course of aphasia, and its impact on vocational outcome, were determined in a group of 351 patients with severe traumatic brain injury TBI. Aphasia was found in 111, the common forms being amnestic 56, 22 39, expressive 10 3, 4 39 and receptive 10 5, 8 39, as found on the first language assessment. No age difference was found between the aphasic and nonaphasic patients. Coma was more common in the aphasics than the non-aphasics 95 and 82, respectively, although its mean duration was shorter. Aphasics had more severe locomotor deficits p 0 01, Fisher test and tended towards more severe cognitive disorders p 0 07, Fisher test. There was no difference between the groups in incidence of behavioural disturbances or occupational outcome. Most of the aphasic patients improved after therapy, and two recovered completely. The presence of aphasia did not have negative prognostic implications for occupational outcome.