The most recent trends in human leukemia, which were discussed at the Ninth Wilsede Meeting, are presented in this volume. The internationally renowned contributors discuss both clinical aspects as well as biomedical studies. They present new information about the biological basis of leukemia which has been gained using the methods of molecular genetics, cell and molecular biology, virology and immunology. The evidence clearly shows both the complexity of leukemia research, as well as the value of basic scientific research in furthering clinical medicine and therapy.