The Elements of Polymer Science and Engineering, Fourth Edition, is a textbook for one- or two-semester introductory courses in polymer science and engineering taught primarily to senior undergraduate and first-year graduate students in a variety of disciplines, but primarily chemical engineering and materials science. Since the publication of the third edition in 2012, the field of polymers has advanced considerably. A key feature of this new edition is the inclusion of new and updated content on such concepts as multifunctional polymers, bioderived polymers, computation modeling, polymer sustainability, and newer manufacturing methods like 3D printing. This edition has also been reorganized to become more aligned with how instructors currently teach the course. Improvements to the book's pedagogy include the addition of more worked examples and end-of[1]chapter problems, and new figures to better illustrate key concepts. This fourth edition will appeal to advanced undergraduate and graduate students in the physics, chemistry, and chemical engineering departments who are taking courses related to polymer science and engineering, as well as engineers new to the field of polymers.