The chapter begins by discussing the major characteristics of wood in terms of structure, major chemical constituents and wood fiber production methods, which is followed by the description of major manufacturing processes for wood plastic composites (WPCs). It then reviews the effects of different variables such as the nature of wood flour (particle size, wood species, and wood flour content), filler–matrix adhesion, characteristics of polymer matrix, processing conditions, performance-enhancing additives, and foaming agents on the physical, mechanical, thermal, and durability properties of WPCs. Finally, the chapter discusses future trends in WPCs including new materials, novel manufacturing techniques, and emerging applications.