Abstract: A method of treatment for synthetic or natural fibre or yarn includes coating the fibre/yarn with a dispersion of carbon nanotubes in a coating composition which is cured by actinic radiation, such as UV, to provide a flexible conductive layer on the fibre/yarn. The liquid coating composition is sheared along the direction of a long axis of the yarn as it is applied to the yarn whereby the carbon nanotubes are substantially aligned prior to curing of the coating layer to provide improved longitudinal conductance. The method provides conductive fibre/yarn, from which anti-static textiles and fabrics can be formed, by treatment of conventional fibre/yarn and in a method with low energy consumption. The improved conductance allows thin or partial (e.g.