Several recent articles have discussed ultrasonographic surveillance of small abdominal aortic aneurysms (AAA). The purpose of this study was to evaluate the impact of lesion size on immediate morbidity and mortality after surgical treatment of AAA. More specifically we investigated whether the mortality rate was lower after treatment of AAA measuring <50 mm in diameter than that resulting from treatment of larger aneurysms. The study population consisted of 309 consecutive patients (289 men and 20 women) who underwent elective surgical repair of infrarenal AAA. Mean age was 69.9 years. Lesion size was measured on preoperative CT scans. Mean transverse diameter was 55 mm (range, 32 to 120 mm). Patients were divided into two groups on the basis of diameter size: group I included 165 patients with AAA <50 mm in diameter and group II included 144 patients with AAA <50 mm. In our experience, morbidity and mortality rates were comparable in patients undergoing surgery for small and large AAA. This finding does not support previous claims that lower operative mortality warrants early surgical treatment.