Hereditary hemorrhagic telangiectasia (Osler's disease) is a well-defined entity transmitted as a simple mendelian dominant. It is characterized by typical vascular lesions of the skin and mucous membranes, and by hemorrhagic manifestations—most commonly epistaxis—appearing in late adult life. A classical and accurate description of this disease was written by Osier<sup>1</sup>; subsequent pathologic and clinical studies have been summarized in a thorough review by Bean.<sup>2</sup>In the last 15 years the occurrence of pulmonary arteriovenous shunts,<sup>3</sup>hemangiomas of the liver associated with portal fibrosis,<sup>4</sup>and reports of aneurysms of the splenic<sup>5</sup>and hepatic<sup>2</sup>arteries have led to the recognition that these patients may have a generalized derangement in blood vessel structure and function. The following report deals with the presence of an aortic aneurysm in a patient with this disease. Such an occurrence has not been previously recorded. <h3>Report of Case</h3> A 77-year-old woman of Norwegian origin was admitted to