Liver surgery has undergone significant technical advancements over the past half-century. These advancements, coupled with greater utilization of some of the unique anatomic and physiologic characteristics of the liver, have led to more extensive liver resections. “Extended hepatectomy” involves resecting more than four Couinad segments. This is most frequently described in two forms—extended left hepatectomy, where the left lobe of the liver and a portion of the right lobe are resected, and extended right hepatectomy, in which the right lobe and a portion of the left are resected. While minimally invasive approaches to extended hepatectomy exist, the current body of literature and widely practiced techniques in extended hepatectomy involve resection through an open approach. This chapter examines extended hepatectomy, discussing perioperative considerations and technical aspects of the surgical approach, resection, and reconstruc tion.