Underside couching is a technique whereby a thread (laid thread) is placed on the surface of the ground material, which is usually held taut in a frame. A second, usually finer thread (tying thread; couching thread) is brought up from the backside of the cloth and then used to encircle the laid thread. The tying thread is returned through the same hole and pulled gently until a loop of the laid thread appears on the back of the material.