Objectives: To determine if immediate surgical repair or regular radiologic surveillance improves survival in patients with small aortic aneurysms. Methods: A total of 1136 people with asymptomatic infrarenal aortic aneurysms (4.0-5.4 cm) with minimal co-morbidities were randomized to standard surgical repair with interposition of a synthetic graft (n = 569) versus radiological surveillance (n = 567). Patients were followed up every 6 months, and those in the surveillance group had CT scan or ultrasound imaging studies. If the aneurysm reached at least 5.5 cm in diameter, or enlarged by 0.7 cm in 6 months, or 1 cm in 1 year, patients in the surveillance group were referred for surgery. The mean duration of follow-up was 4.9 years. Outcomes: The primary outcome was death from any cause, and the primary analysis was by intention to treat. Results: In all, 92.6% patients underwent repair in the immediate surgery group compared with 61.6% repairs in the surveillance group. No significant difference in death from any cause was observed between the immediate repair group (25.1%) and the surveillance group (21.5%) (RR 1.21; 95% CI: 0.95-1.54). Immediate repair did not benefit any of the prespecified groups. Conclusion: No survival benefit is associated with immediate repair of asymptomatic abdominal aortic aneurysms which are less than 5.5 cm.