This multi-author volume provides a useful summary of updated knowledge on polymer composites, practically integrating experimental studies, theoretical analyses and computational modeling at different scales, i.e. from nano- to macro- scale. Detailed consideration is given to four major areas: Part I deals with the structure and properties of nanocomposites. Part II focuses on some special characterization methods and modeling in the field of polymer composites. Processing and applications of macrocomposites makes up Part III, and Part IV deals with mechanical performance of macrocomposoites.