A contact sensor (0, figure 1A), suitable for monitoring activity at the body surface, comprises a contact membrane 1 formed of a knitted conductive fabric and at least one base layer 2 of knitted fabric. In an area contiguous with the sensor, the outermost base layer 3 is knitted with an extra thread which is thicker and forms an area of thicker base fabric layer 4 which allows for the sensor to be urged against the body surface. The sensor may be incorporated in an item of clothing and other wearable items. The application further describes an electronic apparatus for use with a smart garment, a smart garment for use on the human lower body, a means of connecting the sensor to non-fabric electronics and the like, and also a system for the combined use of the sensor and related improvements to the accompanying electronics.
