Since 1971, the Orthopaedic Service at the Massachusetts General Hospital has treated 106 patients with malignant or aggressive bone tumors by wide resection and replacement with frozen cadaveric allograft. Sixty-one of these patients have been followed for over two years (mean, 4.5 years), allowing a comprehensive end-results analysis. In 45 patients, mostly with giant-cell tumors of chondrosarcomas, the resection involved the articular end of a long bone and the replacement not only included bone, but glycerolized (to prevent freezing injury) and articular cartilage. Ten of the segments were intercalary (bone alone) and six involved a combination of bone and metallic joint prosthesis. Patients were graded as excellent, good, fair, or failure, depending principally on functional capacity. End-results analysis in this group showed that five of the 61 patients had either a local recurrence (2) and/or distant metastases (3); in five additional patients the limb was amputated or the implant removed, primarily because of infection (total failure rate, 16.5%). Forty-five (73.8%) had successful transplants (graded excellent or good) and were able to live essentially normal lives. Six of the patients (10%) required a brace or cane but three of these patients were able to return to preoperative work activities. Although the operations were arduous and difficult, and despite a high infection rate (13%) and occasional pathologic fractures (10%), the results compare favorably with other techniques used to restore the skeleton following massive segmental resection. In long-term follow-up, the data suggest that if no complication ensue in the first two years, the results are generally quite good and the grafts show no evidence of progressive deterioration with time.