This updated and revised Third Edition is a practical guide to the study of the microstructure of polymers, stemming from the authors' many years of academic and industrial experience. Introductory chapters deal with the basic concepts of polymer morphology and processing as well as microscopy and imaging theory. The core of the book is more applied, with many examples of specimen preparation and image interpretation leading to materials characterization. Readers learn to use microscopy to characterize a wide range of polymer systems, including fibers, films, engineering resins and plastics, composites, nanocomposites, and polymer blends. Light microscopy, atomic force microscopy, scanning and transmission electron microscopy techniques are all discussed. In addition, the book explores emerging microscopy techniques. It closes with a problem-solving guide that provides a systematic framework for choosing a suitable approach to characterize a polymer microstructure.