Eight patients with chronic Budd-Chiari syndrome resulting from coarctation of the inferior vena cava underwent operation. Transatrial dilatation was of no avail in the first case. The obstructed segment was directly visualized in the subsequent seven cases by a transthoracic, transdiaphragmatic, retroperitoneal approach. In these latter seven cases, severe hourglass constriction of the inferior vena cava was observed just above the right hepatic vein. There was no evidence of inflammation, extrinsic compression, or thrombosis. Retrohepatic cavoatrial bypass with an antibiotic-sterilized aortic homograft was unsuccessful in three patients. Five patients including one with homograft failure underwent successful retrohepatic cavoatrial bypass with a polytetrafluoroethylene graft (20 mm plain in four cases and 16 mm ringed graft in one case). These patients have been followed up for 21 months to 6 years with no recurrence of symptoms. The term coarctation of the inferior vena cava appears more appropriate than membranous obstruction of the inferior vena cava because of the operative findings in the present series.