In this book, outstanding researchers from the US and Japan review recent progress in Epstein-Barr virus research. Most people carry EBV in memory B-cells in a latent stage. Many malignancies such as T/NK cell lymphoma, AIDS-associated B-cell lymphoma, gastric carcinoma and Hodgkin's disease have been causally linked to EBV. The development of molecular biology technique has allowed us to study the roles of individual EBV genes that act in the maintenance and disruption of EBV latency.