It is not often that one one writes the foreword for a book based on a conference which contributed so much to our knowledge in the field of hypertension. During my close association with the International Society of Hypertension from 1978-1982, numerous satellite symposia were held in connection with five interna tional meetings. The specific topics addressed in this volume, the quality of the contributions, and the superb expertise of the contributors make this monograph one of the most outstanding publications that the International Society of Hyper tension has sponsored. Satellite symposia such as the present one serve useful and important functions for our society. They provide a mechanism of getting together the outstanding experts on special subjects for presentation of new data and for a free interchange of ideas. This type of endeavor is one of the most uniquely effective ways of accumulating new knowledge, because the data presented are subjected to critical review and discussion. No textbook or publication in journals can provide the type of critically evaluated information that comes from a small group is a mechanism for scientists to become meeting of this type. Furthermore, it acquainted or better acquainted with one another. All of this is, of course, very provocative and supportive of high quality research, one of the trademarks of the International Society of Hypertension. The conference for this book publication was organized by Drs.