Until the advent of Liver transplantation, it was widely believed that Hepatic Encephalopathy (HE) was usually reversible. The exceptions were the so called "Acquired Hepatocerebral Degeneration cases" which were considered irreversible. Paradoxically, it seems, with liver transplantation, we have seen cases that contradict these rules. Whether the "residual effects" of HE, degenerative brain injury or independent neurological insults are causing post transplant neurological deficits is not easy to discern. As more emphasis is being put on maintaining brain 'status' after liver transplantation, we are finding confirmation of the largely reversible nature of HE. But, enough important exceptions to this rule are occurring to make further research on this topic mandatory.