Wood is a porous, hygroscopic and anisotropic material. This means it takes up water by an adsorption process, hydrogen bonds with it, and shrinks/swells differently across individual planes. Uptake of water also makes it vulnerable to decay. Thermosetting resins have long been used to modify wood to improve a number of properties such as moisture uptake, stability, mechanical properties and decay resistance. The chemical composition of resins, their method of application and wood species used have all been found to influence quality of modification. This review introduces the types of resins used and products manufactured. The proposed mechanisms for stabilisation, methods used to examine resin modification of wood and the resulting changes in wood properties are discussed.