One hundred sixteen arteriographic examinations in 98 patients with Takayasu's arteritis were studied retrospectively to evaluate the extent of aortic and pulmonary disease. Stenosis was the most frequent finding in the aorta and its branches, but occlusion, dilatation, and aneurysms were also seen. Adventitial vascular structures, consistent with dilated vasa vasorum, were observed in five patients (5%) and systemic artery-pulmonary artery communication was seen in six (6%). Twenty-one (70%) of 30 patients who had pulmonary arteriography were shown to have pulmonary artery involvement. Upper lobe pulmonary arterial branches showed abnormalities most frequently; segmental branches, followed by subsegmental branches, were most often involved. The frequency of abnormal findings on pulmonary arteriograms correlated with the number of involved brachiocephalic vessels. Stenotic lesions in the aorta and its branches progressed in five (45%) of 11 patients, and those in the pulmonary artery progressed in one (33%) of three cases. Takayasu's arteritis characteristically involves the systemic and pulmonary arteries, and the extent of arteritis in the major branches of the aortic arch appears to correlate with pulmonary arterial involvement. Both thoracic and abdominal aortographic studies and pulmonary arteriography are necessary to properly diagnose the extent of the disease, and angiography should be repeated for appropriate patient follow-up.