This book aims to introduce veterinary surgeons to a new concept of pain for a better understanding of what pain is and how it occurs. By describing pain pathways and their regulation, as well as the sophisticated therapeutic systems that are currently being developed, this book shows its readers how to interpret pain, and how to identify it as a pathology in itself and treat it as such. The management of chronic pain in companion animals is an area in which there is a significant therapeutic void. In many cases, professionals are unaware of the appropriate approach to managing chronic pain, despite the wide range of pharmacological, surgical, and physical therapy options that act directly on the pain pathways.