Extrahepatic biliary atresia is defined as partial or total absence of permeable bile duct between porta hepatis and the duodenum. The incidence varies from 1:8,000 to 1:10,000. Cholestasis is total and permanent. 131I Rose Bengal test and needle liver biopsy allow correct identification of 95% of cases before surgery. Before the surgical procedure described by Kasai in 1959, all patients died between 1 and 2 years of age. Through the use of different types of Kasai's procedures by experienced groups, 30 to 35% of patients are successfully operated on. In our group, 248 infants underwent surgery, 121 before 1977: 44 (36.6%) are alive at least 5 years after surgery. Growth is within normal limits in all children still alive, even in those who presented with numerous and severe episodes of cholangitis during the first two postoperative years. Portal hypertension was progressive in 23 children with splenomegaly and esophageal varices developing between 1 and 2 years of age. Five patients bled profusely between 2 and 4 years of age: portal systemic shunts were performed in 4. Surgical liver biopsies were performed in 20 children, 5 to 8 years old: cirrhosis was present in all and was micronodular in 13 and macronodular in 7. The most impressive histologic change was absence of biliary ducts or ductules. This histologic finding can be related with percutaneous transhepatic cholangiographic pictures. Despite the abnormal appearance of intrahepatic bile ducts and the constant presence of cirrhosis with portal hypertension, all 44 patients who are alive at least 5 years after surgery seem to lead almost normal lives.