Since medicine is largely regarded as a science, it is expected that medical concepts will remain true and reproducible. Some concepts, however, are not based on medical facts. Some may be suggested by medical data and are often referred to as evidence-based. Some may be based on largely hypothesis and assumptions. Other concepts may be purely anecdotal and have no scientific background. As a result, some concepts of medicine will occasionally be challenged by new or emerging medical data or beliefs. The constant changes in medical concepts help make the practice of medicine more of an art than a science. In addition, new ideas and facts keep medicine mentally challenging and interesting. In this book, we will discuss some of these recent innovations to traditional concepts of medicine. These innovations will remind us that medicine is an art as well as a science and its journey is never-ending.