Ascites, hepatomegaly, and abdominal pain constitute the classic triad of the Budd-Chiari syndrome of hepatic-vein or inferior-vena-cava obstruction. This condition was first mentioned by Budd in the mid 1800s and additional information was provided by Chiari in the 1890s. In nearly two-thirds of patients the exact etiology cannot be determined. The syndrome has, however, been associated with hypercoagulable states, neoplasms, trauma, medications, and congenital abnormalities. The diagnosis is difficult to make clinically; therefore, radiology plays a critical role in the workup of these patients. Nuclear medicine, sonography, CT, angiography, and MRI all provide valuable diagnostic information. These data combined with hepatic biopsy determine which patients should be treated by percutaneous angioplasty or surgery, and also determine the type of shunt to be performed (such as the mesoatrial shunt when the inferior vena cava is occluded or severely compressed). Noninvasive imaging is also useful in the follow-up of patients after both percutaneous angioplasty and surgery.