Eighty-five patients with nonmetastatic, high-grade osteosarcoma of an extremity received intravenous methotrexate and intraarterial cisplatinum and then a definitive surgical resection. The preliminary results suggest that preoperative chemotherapy with a delayed surgical resection is as safe as immediate surgery. More patients are candidates for limb salvage after chemotherapy. The tumor response to the preoperative chemotherapy also has prognostic value. Reducing the postoperative chemotherapy can be dangerous. A high dose methotrexate may not be necessary.