One hundred twenty-nine children (67 girls and 62 boys) less than 16 years of age with pathologically verified osteogenic sarcoma have been seen during the 50-year period, 1909 through 1958. Adequate follow-up information is available on 126 of the patients. The survival rates among children with osteogenic sarcoma are influenced by the degree of malignancy and location of the tumor and the type of therapy administered. Amputation was the primary form of therapy in 101 patients; radiation, was the treatment given 15 patients; excision of the tumor was carried out in only 6. Seven patients were not treated. The authors believe that early amputation is the treatment of choice in patients whose tumors arise in the extremities and who do not manifest evidence of metastasis. No patient with a tumor arising at a site that precluded amputation survived five years, and only one patient treated with radiation therapy survived.