Rosin is an abundantly available natural product composed of around 90% acidic and 10% neutral compounds. Rosin and its derivatives have long been used as tackifiers in adhesives. They have also found other niche applications in inks, varnishes, paints, sealing wax, some soaps, paper sizing; soldering, plasters, food additives, etc. However, many of the conventional applications of rosin mainly utilize the inherent physical properties in various practices.In recent years there has been a growing interest in using rosin acid-derivatives as building blocks in the synthesis of polyesters, polyurethanes, epoxies and curing agents. In addition, rosin acid derived chemicals are also used as nucleating agents, surfactants, drugs and other special applications. This book brings together a collection of scientific articles on recent research and development of utilizing natural chemicals from pine resin as feedstock for polymers and new industrial chemicals. It focuses mainly on the new use of rosin acids, but also covers the applications of other chemicals from tree sap such as terpinenes. This book will provide considerable material for researchers in both academia and industry with the latest developments in the utilization of rosin and terpinenes.