We reviewed 61 patients seen from 1975 to 1994 with a biopsy-confirmed optic chiasm astrocytoma or a characteristic clinical and imaging presentation. The mean age at diagnosis was 72 months, including 30 who were less than 5 years old. The mean tumor diameter at presentation was 31 mm among 54 tumors measured. Tumors involved the optic nerve in 41, hypothalamus in 38, optic tract in 15, and optic radiations in 2. Four patients, all with neurofibromatosis, received no treatment. Forty patients received conventional radiation therapy at a mean age of 89 months. Chemotherapy was given to 19 children and 7 of these were followed for greater than 1 year. Six of these 7 had progressive disease which required subsequent surgery and/or radiation therapy. Thirty-six patients underwent surgery. We restricted our analysis of outcome to those 38 patients followed for longer than 60 months. Development was normal in 13%, mildly disabled in 53%, severely disabled in 21% and dead in 13%. Children were severely disabled or dead in 47% if younger than 5 years at diagnosis, and 21% if older. There was no endocrine dysfunction in 18% and new endocrine failure was seen in 61%. More posterior tumors did not portend a poorer prognosis. Children less than 5 years old had a poorer prognosis. Neurofibromatosis did not have a marked effect on outcome. Intracranial hypertension was an indicator of a poor prognosis. No specific treatment modality was clearly superior in terms of long-term survival or improvement in quality of life.