From March 1984 to April 1991, the Orthopaedics Department of the Clínica Universitaria de Navarra treated 47 cases of malignant bone tumors in young children by limb-salvage surgery. Mean follow-up time was 4.4 years. The histologic diagnoses were osteosarcoma 33 cases) and Ewing's sarcoma (14 cases). All patients were treated following the Cancer Protocol of the Clínica Universitaria de Navarra. We used allograft reconstruction in 26 patients, autograft reconstruction in seven, and nonbiologic material in seven other patients. Thirty-six of these patients are alive currently; 11 have died. The overall survival rate was 76.6%. Three patients suffered local recurrences, and seven developed metastatic disease. The most significant complications were infection in four cases, and osteosynthesis anchorage detachment in eight cases. We believe that with recent medical, surgical, and rehabilitative advances, limb-salvage surgery has surpassed amputation as the primary treatment for malignant bone tumors in young children.