Respiratory system and artificial ventilation are key topics when considering the main aspects of Anaesthesiology and Critical Care Medicine: assisted ventilation techniques are essential to preserve the patient life, but just as any other treatments they can be also extremely pernicious. Scientific research and clinical evidences are equally fundamental in investigating the best methods to provide effective support and increase positive outcomes. It is obviously desirable that this knowledge and know-how are widely shared among scientists and practitioners. With this purpose, the book includes contributions by an international panel of authors and gathers their varied and valuable expertise up to illustrate principles, study results and case experiences on respiratory physiopathology, respiratory mechanics, respiratory functions monitoring, artificial ventilation and diagnostic radiology in respiratory dysfunction failure. We trust it can represent a precious reference for professionals in their ongoing self-improvement process to increase skilfulness. Furthermore, we hope that this book can serve as a useful learning tool for medical students and can contribute to the education of future anaesthesiologists and intensivists.