This proposal entails the interdisciplinary study of multicomponent polymeric glasses to develop a molecular level understanding of macroscopic materials properties. It is an industry-university collaboration involving the fields of chemistry, physics, and engineering. The projects include aspects which range from the synthesis and preparation of materials through a determination of engineering properties to advanced spectroscopic characterization with an overall interpretation assisted by theory and modeling. Systems selected for study are technologically relevant and suitable for study by nuclear magnetic resonance, such as polycarbonates and poly(phenylene oxides), in the presence of diluents. Continued advances in the nuclear magnetic resonance technique allow for new insights into molecular-level motion and structural interactions which bear upon the materials properties of these multicomponent systems. Interpretational frameworks will be sought to relate the nuclear magnetic resonance data to motion and structure in the glasses. A second tier of interpretation is required to relate motion and structure to the macroscopic characteristics of the materials. In both cases, molecular modeling results will assist in the generation of an understanding and also direct the nature of the experimental inquiry.