During the period 1957-1987, 189 patients with neurological signs and symptoms were referred to the Wilson's disease clinic at Addenbrooke's Hospital, Cambridge. The diagnosis was not confirmed in 52 patients. Thirty-three of these 52 patients were sent with a definite diagnosis of Wilson's disease, and 12 had received chelation treatment. Ten patients were labelled as probable Wilson's disease; in nine cases no diagnosis had been made but Wilson's disease was considered a possibility requiring exclusion. One patient only was mistakenly reported to have Kayser-Fleischer rings. The presenting symptoms were tremor (n = 17), involuntary movements (n = 16), difficulty in walking (n = 12), personality changes (n = 4) and epilepsy (n = 3). The mean delay in referral was 8 years (range 6 months to 20 years). Compared with the number of patients with confirmed neurological Wilson's disease seen in this period (137 patients) the referral diagnosis was correct in only 72% of cases. The reasons for error, both clinical and biochemical, are discussed.