Prism Signs are a cost effective mechanism to provide up to 3 messages within a sign. The prisms rotate within a frame, that can be incorporated into a static sign design, to display 1 of up to 3 messages or images at a time. They are made with robust, maintenance free mechanisms capable of providing hassle free message changing for many years. The prisms can be loaded to rotate vertically or horizontally as required. The signs can be controlled wirelessly and integrated into existing systems, including traffic networks.