For some readers, the title of this book will immediately raise the question: Why construct a textbook that deals solely with complications? To answer this inquiry, we must refer to the maxim that each of us агпйуwas taught on the very fi rst day of our medical training: Primum non nocere The discipline of regional anesthesia has seen a major expansion in the last 20 years as a result of better understanding of human anatomy and physiology, and the availability of sophisticateагцядd and reliable technology .