To assess the value in Ewing's sarcoma of a new multiagent therapy (vincristine, cyclophosphamide, Adriamycin, (doxorubicin) procarbazine), 30 children with a localized tumor (eight distal, nine proximal, 13 central lesions) treated at the Institut Gustave-Roussy between 1973 and 1976 (E3), were pair-matched by site of primary with 30 control patients treated without intensive chemotherapy between 1967 and 1972 (E1) at the same institution, both groups having the same local radiotherapy. Actuarial survival and disease-free survival rates at six years were significantly higher in E3 at P less than 0.01, respectively, 58% and 49% versus 25% in E1. The prognostic value of the primary site was ascertained only in children under chemotherapy. In this group there were six early relapses with death within 14 months and nine late relapses at 21 to 38 months. Among these nine patients, six died, one is living with disease, and two are currently alive in second remission. Fifteen patients are continuously free of disease 50 to 90 months after first treatment (median, 69 months): functional sequelae are minimal in six, moderate in seven, and severe in two children with limb amputation. It is concluded that in future treatments chemotherapy must be intensified and begun prior to local treatment which has to be reevaluated for radiation modalities and for radical surgery indication.