Provides a concise, elementary treatment of the most important aspects of rubberlike elasticity, including new theoretical insights and recent experimental results. Taking the viewpoint of the physical chemist or chemical physicist, the author focuses on equilibrium properties (rather than polymer viscoelasticity, for which there is already a huge body of literature). The first part of the book deals with fundamentals, assuming only the basic concepts of physical chemistry; the second addresses more advanced topics, some of which are still under intensive investigation. The more detailed material for both parts has been placed into appendixes.