In this paper the constitutive compressive behaviour of nearly parallel spread-tow textile reinforcement is studied. The striking result of our analysis is that the spread-tow type of reinforcement should obey linear relation between force and deformation. This is in contrast to standard textile reinforcements that obey a power-law type of behaviour. To support the theoretical investigation we have developed an test rig who's chief purpose is to achieve compression between nearly perfectly parallel surfaces. This is achieved using a mechanical arrangement consisting of a ball-joint.