Ion exchange refers to a reversible chemical reaction in which an ion attached to an immobile solid particle is exchanged for a similarly charged ion from a wastewater solution. It is a method of purifying aqueous solutions utilizing solid polymeric ion-exchange resin. Apart from its use in purification of drinking water, this technology is broadly used for the separation of a wide range of medicinally and industrially significant chemicals. Various industries that are dependent on the ion exchange technology comprise power, pharmaceutical, chemical processing, nuclear mining, food and waste water processing industries. This book is a compilation of chapters that discuss the most vital concepts and emerging trends related to ion exchange technology. From theories to research to practical applications, studies related to all contemporary topics of relevance to this subject have been included herein. Those in search of information to further their knowledge will be greatly assisted by this book.