Real-time ultrasonography is utilized in this study to demonstrate most of the large vessels in fetuses from 22 weeks on. Images of the aorta, the coronary ostium, the vessels of the aortic arch, the carotids, the ductus arteriosus, the superior mesenteric artery, the celiac axis, the common iliac artery, the external iliac artery, and the femoral artery are demonstrated. Additionally, images of the subclavian vein, the superior mesenteric veins, the splenic vein, the portal vein, the hepatic veins, the ductus venosus, the renal veins, the iliac veins, and the inferior vena cava, as well as the pulmonary artery and veins and the azygos vein, are presented.