OBJECTIVE The purpose of this article was to prospectively study analyses outcome after staple exclusion of abdominal aneurysms with specific follow-up of the excluded aneurysm. Whether these data may predict behavior of aneurysms excluded from the circulation by transluminal grafting procedures is also addressed. METHODS Staple exclusion of abdominal aneurysms with bypass via retroperitoneal incisions was performed in 100 consecutive patients undergoing elective procedures. Risk factors, clamp time, operative time, transfusions, length of stay, complications, platelets, fibrinogen, and fibrin split products were documented. Duplex imaging was performed quarterly for 1 year after exclusion and at least annually thereafter. Serial measurements of aneurysm size and evaluation for thrombosis was obtained. RESULTS Aneurysm size averaged 5.5 cm. Risk factors included history of smoking (54%), history of heart disease (51%), hypertension (41%), hyperlipidemia (34%), and chronic obstructive pulmonary disease (25%). Clamp time averaged 51 minutes. Forty-eight required no intraoperative transfusion, and 19 needed only autologous blood; the average 24-hour transfusion was 313 cc. Length of stay averaged 11 days, with a median of 8 days, and correlated with age, aneurysm size, and risk factors. The 30-day mortality rate was 4%. Death was associated with longer operative and anesthesia times and with age and risk factors. As calculated by life-table analysis to 5 years, 96.8% of aneurysms thrombosed. No aneurysm expanded, became symptomatic, nor ruptured. Perioperative platelet, fibrinogen, and fibrin split product assays show no evidence of disseminated intravascular coagulation or consumptive coagulopathy. CONCLUSIONS Staple exclusion and bypass of abdominal aneurysms as described in this study is safe and effective. There has been neither aneurysm expansion nor rupture, and the technique reliably leads to thrombosis of aneurysms without coagulopathy.