Four cases of aortoenteric and paraprosthetic-enteric fistulization are presented. Particular emphasis is placed on the distinct clinicopathologic characteristics of these two types of graft-enteric fistula which, if unrecognized, result in an almost invariably fatal outcome. Available data as well as the cases herein reported clearly demonstrate the need for a higher index of suspicion and strict adherence to well-established principles for management of complicated aortic grafts. Best results can be obtained with prompt surgical intervention, total removal of all prosthetic material and lower extremity revascularization by means of extra-anatomic bypass.