Surgical manipulation to achieve stenosis or occlusion of portocaval shunts in 7 dogs resulted in disappearance of signs of central nervous, gastrointestinal, or urinary dysfunction. Results of blood chemical analyses and hepatic function studies as well as hepatic cellular architecture returned to normal or near normal within several months. Cranial mesenteric angiography was done on 4 dogs following corrective surgery; there was evidence of improved hepatic-portal circulation in 3 of the dogs and complete shunt obstruction in 1 dog.