Fifty-six patients with RDC schizophrenia (42) or schizoaffective disorder (14), of two to 20 years' duration, were assessed for neurological 'soft' signs and cognitive impairment when in a stable condition--the 'outcome'. Neurological dysfunction (46% of 50 examined patients) was associated with a history of developmental abnormalities, but was unrelated to outcome, psychiatric symptoms, or treatment. Deficits in particular cognitive fields were related to two independent factors: overall severity of residual psychiatric disorder (outcome) and neurological dysfunction. There was no relationship between the size of the lateral brain ventricles on CT scan and either 'soft' signs or cognitive impairment. The findings do not provide evidence for an association between the presence of organic brain disorder (as indicated by the joint occurrence of neurological dysfunction and cognitive impairment) and either poor outcome or particular symptoms of schizophrenia.