Action of irrigants in the root canal system is indespensable. Despite technological advancements, endodontists are yet to achieve predictable disinfection of root canals. The need of the hour is to relentlessly pursue development of newer solutions and techniques in the science of endodontic irrigation in order to achieve absolute disinfection of complex root canal system. With the irrigants available to us today, we need to use a combination of two or more irrigants to achieve acceptable results but this requires careful selection based on thorough understanding of the chemistry and mechanism of action of various irrigants as they may interact. This book reviews the chemical interactions between the various commonly used irrigants in Endodontics.