Patients with chronic gastrointestinal bleeding with no source found after standard radiographic and endoscopic procedures are diagnostic challenges. Since angiodysplasia is a frequent cause of such bleeding, selective angiography has become an essential diagnostic tool in identifying arteriovenous malformations (AVM) of the large and small bowel. In addition to preoperative identification, some method of intraoperative localization is essential to assure removal of the involved segment. In a patient with a 7-year history of gastrointestinal bleeding from an AVM of the small bowel, a technique of preoperative angiographic catheter placement with intraoperative confirmation of catheter position proved a useful way to find such small bowel lesions and insured adequate but not excessive resection.