A new concept of hepatic segmentation along with the Glissonean pedicle tree, and the basis of hepatic resection by the Glissonean pedicle transection method are presented. The portal triad continues from the hepato-duodenal ligament to the intra-hepatic portion as the Glissonean pedicle. That is, the artery, portal vein and bile duct, together with connective tissue, are sheathed by the peritoneum to form a fibroid bundle. The entire length of the primary branches of the Glissonean pedicle and the origin of the secondary branches are located outside the liver and the trunks of the secondary and more peripheral branches run inside the liver. The ramification pattern of the tertiary branches which branch out from each secondary branch is different from patient to patient. The liver is nourished by the secondary branches of the Glissonean pedicle. Each secondary branch feeds one segment. The liver can thus be separated into three segments and an additional caudate area. The area fed by each one of the tertiary branches is cone-shaped; fermed a "cone unit". Each segment conists of six to eight cone units. In limited resections, the number of cone units to be respected is adjusted and the tertiary branches which feed these areas must be transected selectively through a hilar or a parenchymal approach. To date we have experienced no complications with this procedure, employed for 832 patients with hepatocellular carcinoma.