Percutaneous tumor ablation techniques are now well established in the curative or pall- tive treatment of patients with primary or secondary malignant tumors of the liver. Radioembolization is a newly developed technique which takes advantage of the synergy of endovascular embolization and ofbrachytherapy in the treatment of cancer. It offers new perspectives for achieving local control of tumor growth with a low rate of complications. This book is the result of an intensive and successful collaboration between two le- ing European centers in interventional radiological oncology which have rapidly acquired extensive experience with this new technique over the past few years. I am very much indebted to the editors, Professor Bilbao and Professor M. Reiser, for their superb efforts in putting together the concept and outline of this volume, as wells as for the very short preparation time needed for its final publication. I thank them and the collaborators from their team, who actively participated in the compilation of the various chapters, for their excellent work. This outstanding volume covers all basic and clinical aspects of radioembolization of the liver very comprehensively. Thus it offers a complete practical guide to interventional radiologists wishing to become familiar with this highly interesting approach to the tre- ment of malignant liver tumors. It will undoubtedly be of great interest also to therapeutic radiologists, medical onco- gists and oncological surgeons, since it will enable them to better design the optimal tre- ment strategy for their patients.