Abstract: A ship security device is disclosed including a barrier and a panel. The security device may transition between a first configuration and a second configuration. In the first configuration the security device is unassembled and at least the barrier may be arranged in a storage configuration in which the barrier curves or bends through a first angle, and in the second configuration the security device is assembled in an arrangement for use, in which the security device may be assembled around a rail. In the second configuration at least a part of the panel is orientated to be substantially vertical, and the barrier is curved, bent or folded through a second angle, which is greater than the first angle, to protrude away from the panel in a horizontal direction, perpendicular from a plane extending vertically through the rail, to provide an overhang on an exterior side of the rail.