Background and Objectives: Soft tissue sarcomas (STS) of the true pelvis are rare tumors and there is little information in the literature related to pelvic STS. The purposes of this review were to understand the anatomic extension of these tumors to better plan surgical treatment and to determine the outcome of these patients. Methods: Eighteen consecutive patients presenting between 1987 and 1995 with soft tissue sarcomas involving the true pelvis were retrospectively reviewed at minimum follow-up of 18 months. Cross-sectional imaging was reviewed for each patient to determine the anatomical location of the lesions. Results: The tumors were confined to the true pelvis in 4 patients, extended to the retroperitoneum in three cases, and extended to the thigh in 11 patients. Adjuvant radiation was administered to all but 2 patients who had received radiation to the region in the past and all patients underwent surgical resection (local resection in 13 patients and hindquarter amputation in 5 patients). Surgical resection had a high rate of morbidity and complications including positive resection margins in nine individuals. Of the 18 patients, 11 died at a mean time of 15.5 (2–58) months from surgery, 4 were alive with evidence of disease at a mean time of 44.3 (18–68) months, and 3 were alive with no evidence of disease at a mean time of 57 (43–71) months. Conclusions: Soft tissue sarcoma of the pelvis is fortunately a rare disease with a high risk of local and systemic disease progression despite treatment with irradiation and surgical resection. J. Surg. Oncol. 2001; 77:8–14. © 2001 Wiley-Liss, Inc.