THE RISK associated with hepatic lobectomy has diminished as better understanding of hepatic anatomy and physiology has developed. However, basic problems in hemostasis are still unsolved, and the operative hazards are still considerable.1-4 Because experience and progress in this field are limited by the relative rarity of lesions requiring hemihepatectomy, there is justification for reporting a relatively small series of cases. This report presents some observations about anatomic factors related to problems in hemostasis and some conclusions about indications for total hepatic lobectomy, based on experience in the surgical treatment of 11 adult patients. Anatomy The true lobulation of the liver is related to the branching of vascular afferents and biliary ducts at the porta hepatis.5 The plane of division between right and left hepatic lobes passes between the gallbladder fossa and the fossa venae cavae. The middle hepatic vein lies between the right and left lobes and