Aneurysms arising in an aberrant subclavian artery are rare but constitute a potentially lethal condition that can be treated successfully when appropriately identified. Virtually all patients have a superior mediastinal mass that may be asymptomatic, but usually patients have symptoms of dysphagia, chest pain, or shortness of breath. An accurate diagnosis can now be made noninvasively with computerized tomography. The presence of an aneurysm of an anomalous subclavian artery is an indication for surgical resection. Resection of the aneurysm may be approached through either a right or left thoracotomy. Reestablishment of continuity of flow to the right subclavian artery decreases the risk of ischemia of the extremities and prevents development of the subclavian steal syndrome. Reestablishment of flow to the right subclavian artery is more easily performed through a right thoracotomy incision but this approach limits control of the aorta at a possibly treacherous connection between aorta and aneurysm. In such circumstances a preliminary extra-anatomic reconstitution of flow to the right subclavian artery followed by a left thoracotomy may be preferable. A 67-year-old woman is described who had resection and grafting of an aneurysm in an aberrant right subclavian artery together with a review of the literature and a discussion of problems in the management of patients with this condition.