In a retrospective cohort study, the level of education attained by 2,283 long-term survivors of childhood and adolescent cancer was investigated and compared with that of 3,270 sibling controls. Survivors of central nervous system tumors were significantly less likely than controls to complete eight grades of school or, if they completed high school, to enter college. No significant differences in educational achievement were found for survivors of non-central nervous system cancers. The educational deficit of survivors of brain tumors was especially striking for tumors of the ventricles or cerebral hemispheres, and the deficit was more severe for those treated with radiation therapy than by surgery alone. Early age at diagnosis of a central nervous system tumor was associated with a larger educational deficit than late age at diagnosis. These findings are reassuring for the majority of long-term survivors of childhood and adolescent cancers given therapies used prior to 1975.