Millions of people suffer from chronic persistent pain. The medical terms are confusing so I have attempted to simplify the language of pain, so that my explanations are more easily understood. My idea of beginning with a case report is a method of hooking and making the explanation more alive and real. This book is aimed at Doctors, Medical students, nurses and the lay public so that they can get a basic understanding of problems they may come across. The case histories are of real patients with real problems. If the patients have behavior that is not appropriate, they should be treated with respect and one must try to help them to solve the chronic persistent pain problems so that they are able to function normally. All the case studies are about actual people but their names have been changed. The medical terms have been written in simple terms so that they may be easier to understand, when possible. The generic and trade names of drugs, in brackets, have been used to make them available to students or interested parties.