The long-term prognosis in 316 children (aged 0-14 years), in whom intracranial tumour was diagnosed during the years 1935 to 1959, has been evaluated. 196 patients survived for longer than four weeks after diagnosis or operation, and a total of 74 patients survived to follow-up after an observation period of 15 to 40 years. The prognosis for children with intracranial tumour is dependent on the age at which the diagnosis is made--the older the child the greater his chance of survival. However, in this study, the older-age group (10 to 14 years) also had the greatest number of recurrences after more than 10 years. A clinical history of more than six months is associated with a better prognosis. Long-term survival was independent of whether the tumour was supratentorial or infratentorial, but all patients with deep cerebral tumours and brain-stem tumours died within the observation period. Patients with intrapontine tumours had a very poor quality of life up to the time of death, whereas the majority of patients who survived for more than one year before recurrence were almost free from symptoms during the interval.