This book describes the emerging phenomena and associated conceptual understanding in the field of nonlinear polymer rheology. This book focuses on the core content of polymer rheology and most importantly, describes what happens when polymeric liquids are subjected to a variety of different forms of deformation and flow. The author, Shi-Qing Wang offers new insights that are extremely useful for advanced undergraduate and graduate courses. In this book, he proves that shear homogeneity, the basic foundation for experimental rheometry requires modification. Although polymer rheology has a history of literature, this book uniquely exposes elementary ideas like the initial elastic response of viscoelastioc materials to sudden external deformation providing a fresh treatment of the subject.