We reviewed our experience on the surgical treatment of anastomotic false aneurysms from 1979 through 1990: two groups of patients were identified. Group 1 (31 patients) included patients who had been previously operated on at our Institute and then routinely followed-up with physical examination and ultrasonographic studies. The incidence of anastomotic aneurysm in this group was 4.03%; the interval between insertion of the prosthesis and detection of the false aneurysm varied from 5 to 144 months, with a median interval of 58 month. The surgical treatment of choice (false aneurysm resection and graft interposition) has been successfully performed (97% of cases) without mortality. Group 2 (8 patients) included patients with complications of false aneurysm (emergency operations); in this group radical treatment was not always applicable; mortality and amputations rate were significantly increased (respectively 25% and 37%). We conclude that, after prosthetic reconstructions, only a careful long-term follow-up (also with use of ultrasonic and/or CT-scan studies) may allow reduction in morbidity and improvement in late survival.