Between 1964 and 1977, 94 patients with Ewing's sarcoma of bone were treated at the National Cancer Institute. They received 5000 rad to the whole bone and progressively more aggressive chemotherapy protocols. The patients were divided according to site of primary lesion into central, proximal and distal lesions, with 19%, 33% and 57%, respectively, alive and well. Of 28 patients autopsied, 11 (39%) had had a pathologic documentation of local recurrence. An additional three patients had a biopsy-proven local recurrence, for a total pathologically proven rate of 14/94 (15%). A total of 16/94 (17%) patients had clinical evidence of local recurrence. The overall local recurrence rate (clinical plus pathologic) was 22/94 (23%). This rate varied according to the site of the primary and was 14/42 (33%) for central, 6/24 (25%) for proximal, and 2/28 (7%) for distal lesions. The local recurrence rate did not change significantly either with the more aggressive chemotherapy regimens or with the presence of metastases at presentation. The local control rate is high (93%), with good functional results in the distal lesions, and no changes are needed in radiation therapy dose or volume. Control is not as satisfactory for central and proximal lesions and efforts need to be made to increase control at these sites. We are at present attempting to define more accurately the extent of soft tissue disease, increasing the dose to 6000 rad for central lesions, and using a more aggressive chemotherapy program, in the hope of increasing the local control in these more aggressive tumors.