Abstract: The present invention discloses a reinforcement product for use in cement boards and a method of manufacturing said product and of manufacturing cement boards using this product.The reinforcement product of the present invention comprises cross-layered webs of plastic fibres with a preponderance of fibres laid in the trans-axial direction, and continuous filaments or fibrillated tapes located between the layers to impart a high degree of strength in the axial direction. The cross-layered web and the filaments or tapes are compacted to form a reinforcement product which can be rolled up and handled for further processing on cement board forming machines. The webs of plastic fibre are formed by monoaxially orientating on extruded sheet of plastics material in axial direction, then fibrillating the sheet to form a cohesive fibre mass which is cut into lengths and carded to break up the film into a coarse fibrous mass which when stripped from the carding machine forms said plastic fibre web.