Seventy-six patients with localized Ewing's sarcoma who received primary treatment at M.D. Anderson Hospital from 1948 through December 1975 were reviewed. Patients have been divided into four groups according to the different treatment regimens they received: Group I, moderate dose radiotherapy alone; Group II, high dose radiotherapy alone; Group III, radiotherapy plus vincristine and cytoxan; and Group IV, radiotherapy plus vincristine, Adriamycin, cytoxan and actinomycin. The problem of local recurrence appears to be solved with combined chemotherapy and radiation therapy with only one of 36 patients having a recurrence at the primary site in Groups III and IV. Multimodal therapy is the preferred treatment to obtain control of the primary lesion by radiation therapy while preserving good function. However, the major cause of failure remains distant metastases, 19 of 36 (53%) in Groups III and IV. In addition, 4 of 10 patients who have survived over 5 years have developed osteogenic sarcoma.