Wood plastic composite (WPC) is a term which refers to a composite containing wood in any form, combined with either thermoplastics (which can be re-melted) or thermoset plastics (which cannot be re-melted once set). Thermoplastics include polyethylene and polypropylene which are used in numerous non-structural applications, such as bottles and containers. Thermoset plastics are formed from resins such as polyester and epoxy. Solid recycled plastic lumber (RPL), which is usually made from waste plastics without any wood or fibre element, also competes in this non-structural role. This Digest describes the manufacture of several types of WPC and their strength, stiffness and durability. Although their strength is low in comparison with timber, WPCs have been used for decking and bridges. Their properties are compared with those of fibre reinforced polymers (FRPs). 4 pages.