To the beginner, the brain and spinal cord can appear discouragingly complex in form and function. This book is intended for those who have almost no knowledge of the central nervous system, but wish to comprehend the most essential principles of how it is constructed and the way it works. Much of the book is designed to provide a structural and functional insight into how the system might fail and how damaged components might be recognized. The discussions are based on a generalized mammal, with occasional specific details of man and domestic animals. The core material exploits every possible way of saving time and labour in grasping the basic aspects of structure and function. More advanced passages (presented in smaller typeface) are relevant to research students and clinicians, especially those in veterinary practice.