The posterior fossa is a common site of occurrence of astrocytic tumors in the pediatric population. The two distinct subgroups comprising these tumors are cerebellar astrocytomas and brainstem gliomas. The cerebellar astrocytoma commonly presents with signs and symptoms of increased intracranial pressure. These tumors are generally amenable to total surgical resection, and carry an excellent prognosis. Brainstem gliomas are a hetero¬geneous group of tumors of which the diffuse pontine glioma is the most common. These tumors are inevitably glioblastoma multiforme, and carry a dismal prognosis. In recent years, subgroups of brainstem tumors have been identified, which are more focal in nature, are of a more benign histology, and carry a better prognosis. These tumors may be amenable to surgical resection. © 1995 Lippincott-Raven Publishers, Philadelphia.