A method of applying a powder coating to a non-metallic substrate such as a length of a lignocellulosic material, e.g a length of wood, is disclosed. The substrate is impregnated or has applied to the surface thereof, a composition containing a pre-accelerated, unsaturated polyester resin containing a latent catalyst therefor, either dissolved in a suitable non-aqueous solvent or mixed or dispersed in water. Thereafter the non-aqueous solvent or water is removed, and the substrate is placed in an electrostatic field or in a fluidised bed and a powder coating composition is applied thereto. The substrate is then subjected to an elevated temperature to polymerise and/or cross-link the polyester resin in or on the substrate and to cure the powder coating composition to form the powder coating. The result is a product with a decorative powder coating which may be used for many purposes.