This chapter presents modern terminology of liver anatomy and resection. It is also an introduction to surgical anatomy of the liver.No single chapter can describe the anatomy of the liver in detail. The intention is to provide an anatomical foundation for performing liver resection and a terminological foundation for describing those procedures so that surgeons around the world can understand each other when they communicate orally or in writing. Surgically unimportant anatomic features are omitted. The chapter has two parts. The first part deals with terminology; the anatomical concepts introduced are those necessary to explain the basis of the terminology selected.The second part deals more formally with surgical anatomy.