The role of ifosfamide as first-line chemotherapy treatment of non metastatic Ewing's sarcoma of the extremity is still under discussion. The purpose of this paper is to report the results achieved in a neoadjuvant protocol (REN-3) in which ifosfamide, added to the conventional VACA regimen, was employed since the induction phase. Induction chemotherapy consisted of vincristine, cyclophosphamide, doxorubicin, actinomycin-D and ifosfamide. After local treatment, patients received the drugs used in the induction phase and etoposide. Between November 1991 and November 1994, 61 patients with non metastatic Ewing's sarcoma of the extremity were treated. Forty-nine patients underwent surgery and 73.5% of them had a good histologic response. At a median follow-up of 60 months (range 32-76), 48 patients (79%) remained continuously disease-free. The 5-year event-free and overall survival were 77% and 87%, respectively. These results were significantly better both in terms of histologic response or event-free and overall survival than those obtained in 58 patients with non metastatic Ewing's sarcoma of the extremity treated in a previous protocol (REN-2) in which the same drugs were used, but ifosfamide was employed only in the maintenance phase. The present study suggests the importance of early use of ifosfamide in the treatment of patients with non metastatic Ewing's sarcoma of the extremity.