Cellular therapy with liver stem cells and their progeny, including bone marrow cells, is a promising new approach that will contribute significantly to the treatment of liver diseases. The existence of the liver stem cell had long been debated, but it is now generally accepted that the liver contains cells with stem-like properties and that these cells can be activated to proliferate and differentiate into mature hepaytes under certain conditions. There is also a substantial body of evidence to suggest that oval cells are involved in liver regeneration as they differentiate into hepaytes and biliary cells. This book is a collection of work on stem cell and liver regeneration, initially delivered at the 14th Yamaguchi (Japan) Symposium on Liver Disease. Its nine chapters present the most recent data about basic and clinical research in hepatology in Japan and other countries, providing a valuable resource for researchers and practitioners alike.