To explore whether the adoption of a systematic attempt to perform wider resections may lead to prognostic improvements in retroperitoneal soft tissue sarcoma (RSTS). Two hundred eighty-eight consecutive patients who were surgically treated at a single referral center were analyzed. Because a shift toward a systematic, more aggressive surgical approach (ie, liberal en bloc resection of adjacent organs) was in place from 2002 onward, patients were divided in two groups accordingly. Overall survival, crude cumulative incidence (CCI) of local recurrence, and distant metastases were estimated. Univariable and multivariable analyses were carried out. Patients who underwent operation in the early period had a 5-year local recurrence rate of 48% compared with 28% for patients who were treated in the recent period. The number of distant metastases was greater in the recent group (22% v 13%), and overall survival was similar. In addition to the period of treatment, important independent determinants for local recurrence-free survival were histologic grade, histologic subtype, and radiation therapy. Overall, liposarcomas and grades 1 to 2 tumors had the greatest local benefit at 5 years. In a single institution, the adoption of a policy of more liberal visceral en bloc resections was paralleled by greater local control. This benefit might translate into a prognostic improvement only on a longer follow-up for patients with a more indolent disease, whereas systemic failures seem to be the main problem in high-grade tumors. Radiation therapy could add some additional benefit to local outcome and possibly to survival.