The feasibility of radical surgery for astrocytomas of the optic chiasm/hypothalamus has been reported by several groups. Such surgery carries significant risks, however, including permanent damage to the pituitary gland, optic apparatus, hypothalamic structures, and carotid arteries. The benefits of radical surgery, both in terms of efficacy and toxicity, should, therefore, be evaluated against standard therapy, as is usually done for new chemotherapeutic protocols. To this end, a retrospective review was performed of 33 patients treated at Children's Hospital of Philadelphia between 1976 and 1991 who met criteria that would have made them eligible for radical surgery in many centers today, but were treated with either no surgery or conservative surgery (< 50% resection) or biopsy followed by adjuvant therapy with local radiation therapy (29 patients) and/or chemotherapy with actinomycin-D and vincristine (18 patients). The review encompassed all children with a globular enhancing mass of at least 2 cm in the hypothalamic/chiasmatic region, no evidence of optic nerve involvement or involvement of the optic radiations by computerized tomography or magnetic resonance imaging, and follow up of at least 3 years. All but one patient had tissue confirmation of a low-grade or pilocytic astrocytoma. Thirteen of the patients were 2 years of age or younger at diagnosis. Five individuals died: three of tumor progression, one of acute shunt malfunction, and one of intercurrent infection. The remaining 28 were alive at last follow up, a mean of 10.9 years from diagnosis. Twenty-three surviving patients have functional vision in at least one eye, 12 require no endocrine replacement, and 16 are in or have completed schooling with regular academic requirements. If radical surgery is to become standard care for children with low-grade astrocytomas of the hypothalamic/chiasmatic region, long-term survival and functional outcome will have to equal or surpass those of historical controls who were treated conservatively.