Ischemic colitis after aortoiliac vascular reconstructions represents a seldom but life-threatening postoperative complication (incidence: 1.6%, mortality rate: 50-70%). The authors present a retrospective evaluation of 10 cases observed in a consecutive series of 1121 reconstructive aorto-iliac procedures. The incidence of ischemic bowel complications was 1.3% in the group of abdominal aortic aneurysms but only 0.6% in the group of arterial occlusive disease. The pathogenesis including new approaches of prophylaxis, diagnostic and therapeutical measures are discussed. The risk of ischemic damage to the bowel may be best assessed from the preoperative aortogram (special vascular patterns), the intraoperative stump-pressure measurement in the inferior-mesenteric artery and the pre- and postoperative PB-Index. In contrast to earlier reports the leading clinical symptom is an unexplained prolonged gastrointestinal paralysis during the first postoperative week. Early diagnosis is most important and best realized by the routine use of colonscopy in all risk cases in the first 48 h. Such an aggressive diagnostic approach offers the possibility of early relaparotomy in a pretoxic stage and a better outcome for the patient than heretofore with a median delay of 11 days between vascular reconstruction and relaparotomy.