Important progress has been achieved during the past decade in the radiological diagnosis of congenital and acquired diseases of the kidneys and the urinary tract in infants and children. This book sets out to provide a comprehensive overview and a much-needed update of our knowledge in this field,with a special focus on the progress that has followed from the clinical introduction of the new sectional modalities: color Doppler ultrasound, spiral CT and MRI. I would like to express my great appreciation and sincere thanks to Richard Fotter, Professor and Chairman of the Department of Radiology at the University of Graz,Austria, not only for his success in engaging the leading experts in the field for this volume but also for his superb coordination of the preparations for publication according to the planned schedule. This volume should be particularlyuseful not only for residents in trainingandpediatric radiologists but also for general radiologists, active in community hospitals, whoare regularly confronted with many of the problems discussed in this book.Moreover,it is evi­ dent that pediatricians and pediatric surgeons will also greatly benefit from studying the contents of this book in order to help them optimize the management of their young patients. I am convinced that this volume will meet with the same great success in the medical community as many of its predecessors in from this series.