A contact sensor (0, fig 1A), suitable for monitoring activity at the body surface, comprises a contact membrane (1, fig 1A) formed of a conductive yarn on the surface of at least one base layer 2 of knitted fabric. The contact sensor may form part of a wearable item. An electrical connection point is formed wherein the contact membrane connects by means of a pressure contact with a conductive pad (10, fig 5A) on an external surface of a further item such as an electronic monitoring apparatus. The electronic apparatus may be housed in a pocket on the surface of the wearable item. The pocket restricts movement of the further item and helps maintain electrical contact.
