From 1977 to 1988, 81 adult patients with localized soft tissue sarcomas at different sites received postoperative external beam radiotherapy (55 Gy median dose) following primary conservative surgery. Sixty were new referrals after primary surgery and 21 were irradiated after excision of recurrent disease. With a median follow-up of 4 years (range: 2-13) the 5-year overall survival (Kaplan-Meier) and local control were 55.5% and 56% respectively, while 5-year disease-free survival is 49%. There were 26 (32%) local relapses and 22 (27%) distant failures. Local recurrence was the sole pattern of failure in 16 patients (20%). Functional and cosmetic results were good to excellent in most cases. In our series local control is the main prognostic variable influencing survival (P less than 0.0001), and its probability seems to show a link with the type of surgical procedure, with a trend (P less than 0.13) in favor of wide total excision. Postoperative radiation therapy represents an acceptable treatment strategy for ASTS, but further improvements are expected from future controlled clinical trials, aiming at the achievement of the definitive cure of these tumors.