The treatment results in 18 patients with medulloblastoma were reviewed retrospectively. All patients were treated postoperatively with simultaneous craniospinal irradiation. Forty-four percent of the total group were alive without evidence of disease. Six of the 12 patients eligible for analysis at three years after completion of treatment had continuous disease-free survival. Six patients with intracranial recurrence received a second course of whole-brain irradiation, and two of these are alive.