The aim of the INTERNATIONAL YEARBOOKS OF NEPHROLOGY is to publish every year a volume to keep nephrologists up to date on all the rapidly changing areas of nephrology. Each volume will be published by the end of each calendar year which corresponds with the annual meeting of the American Society of Nephrology. Each issue of the INTERNATIONAL YEARBOOKS OF NEPHROLOGY will be divided into sections; each section will have different primary focus every year, depending upon what area is of greatest interest at the time. In other words, each annual volume will deal with what is truly current in nephrology. All the authors appointed for the chapters of the INTERNATIONAL YEARBOOKS OF NEPHROLOGY are known experts in the field who will give an objective review of the topic up-dating the readers on the world-wide literature. A crucial point for the success of the INTERNATIONAL YEARBOOKS OF NEPHROLOGY is the list of the references at the end of each chapter. We have asked all authors to provide a complete, accurate and up-to-date list of important references. In order to guarantee the most up-to-date yearbook, very rapid production is mandatory. Rapid publication can be obtained only with camera-ready manuscripts for direct photo-offset reproduction. Thus we have agreed to use photo-offset printing for the series. For the first issue of the series, the INTERNATIONAL YEARBOOK OF NEPHROLOGY 1989, the Editorial Board has focused attention on the latest and most important scientific and clinical advances in nephrology.