‘Click’ reactions are a unique class of versatile synthetic tools used in organic and polymer chemistry to develop new materials. The high efficiency of the click reactions, combined with their easy and straightforward execution, have made them an inevitable tool for the development of a variety of advanced polymer materials with tailor-made architectures and stimuli-responsive features. This book aims to give a comprehensive overview and introduction on the use of ‘click’ chemistry in polymer science, including ‘click,’ ‘click-like,’ and reversible ‘click’ (or ‘un-click’) approaches in the design of macromolecules. Moreover, it will outline recent progress in utilizing different ‘click chemistry’ in the development of functional polymer materials for various applications, such as self-healing, hydrophobic, shape-memory, and bio-based materials. Written and edited by leading experts in the field, chapters cover the use of different ‘click’ reactions, like azide-alkyne, Diels-Alder, Alder-ene, thiol-X, electrophilic substitution, and trans (esterification/amination) reactions, in polymer science. It will also cover the concept of ‘trans-click’ reactions, which have come to the foreground on account of improving the exchangeable efficiency of covalent bonds in covalent adaptable polymer materials. Recognizing the present state-of-the-art, this book will be a suitable reference handbook with a valuable resource of information for students of all levels, for learning and teaching endeavors, and for researchers and scientists working on the next generation of advanced polymeric materials.