Mitral regurgitation is today the second most common valvular pathology in industry countries. With changing demographics it will increase in prevalence in the next decades. Since the early days treatment of mitral regurgitation the area has undergone major changes, and in the past 15 years we have experienced a dynamic evolution. Minimally invasive approaches have entered clinical practice, and new surgical procedures are on the horizon. Most recently we have seen the development of interventional approaches to the disease, thus generating interest in the disease also by interventional cardiologists. Formerly a pure "surgical" disease, mitral regurgitation has developed into a multi-disciplinary area. These recent developments in treatment of heart valve disease emphasize the need for an integrated approach while keeping innovation in the context of the current state of the art. This book focuses specifically on mitral regurgitation, integrating anatomical, physiological, cardiological, and surgical aspects in an updated form. It was written by a multidisciplinary team and offers a condensed but detailed overview, aiming at a broad spectrum of health care professionals.