The invention of the stethoscope by René Laennec represented, without a doubt, a landmark in modern medicine. Since the publication of his work in 1819, improvements in the technique and equipment have been described but none has represented a substantial change in the essence of the method. At this moment, one of the most popular acoustic stethoscopes is the model designed by Littmann, in 1960! Recently, we have published in the "International Journal of Cardiology" a new auscultatory method of adult heart exploration, based on the Doppler phenomenon. Contrary to other improvements on Laennec technique of auscultation, the Continuous Wave Doppler (CWD) exploration is based on totally different physical principles, and it is, therefore, a novel and original approach to the patient physical examination.This book aims to share our discoveries and observations using this method and, as it is something totally new, we do not intend to exhaust the subject. On the contrary, our objective is to describe the theoretical foundations, technique and the normal findings of CWD auscultation, to help the readers make their own experience. We wish that future editions of this book will be completed by new observations, applications or other progresses developed by colleagues. It is our hope that the book will be useful to our colleagues.