Twenty-six patients with Gilbert's disease (congenital, non-haemolytic unconjugated hyperbilirubinaemia) were analysed regarding their clinical presentation, age at onset of symptoms, sex, frequency of symptoms, family history, race and religion. Seventy-three per cent were men, the mean age at onset of symptoms was 21 years, and frequency of symptoms ranged from 4 times a year to once every 5 years. The symptoms, which were extremely vague, included the following: recurrent asymptomatic jaundice in 74%, malaise in 66%, asthenia in 65%, and vague abdominal distension in 52% of patients. Eight per cent of patients were totally asymptomatic. There did not appear to be any particular race or religious group with a higher incidence of the disorder. No abnormal clinical features apart from mild jaundice were detected. The entirely benign nature of the syndrome is stressed, and a normal life expectancy is the rule. The avoidance of prolonged fasting is the best therapeutic measure, although enzyme induction by phenobarbitone therapy may have some place in the management of symptoms.