Unlike traditional textbooks, this book is edited as a series of topical seminars given by active researchers. The order of chapters is topic related, rather than the traditional layout of the pain textbooks, which is from periphery to the brain, and from basic to clinic. Most of topics are selected based on the recent progress as well as basic discovery at neurobiological levels in terms of our understanding. Many particular areas related to pain and analgesia are not covered, in part due to either the lack of molecular and cellular understanding of the process or the limit space.