The author sifted through an encyclopedic amount of information to provide a selection of more than 550 microscopy pictures resulting from the observation of multiphase polymer-based materials. These illustrations include micro and nanopolymer blends, micro and nanocomposites, micro and nano phases in copolymers, thermosets, and thermoplastic blends that were intensively developed over the past decade. Each picture includes a detailed explanation of how to attain these materials, how the samples were prepared, and how the observations were conducted. The book examines the various microscopic tools employed for the investigation of the phase morphology, highlighting the advantages and disadvantages of each. It provides a practical, straightforward approach for dealing with the microscopic observation of phase morphology in multicomponent polymer blends and nanocomposites.