A desk top system which has a basic superstructure upright that permits attaching cantilevered supports for supporting desk tops, pedestals, and the like so that they can be adjusted easily and conveniently relative to one another. The pedestals can be removed if the pedestals interfere with the movement of the feet of a user when the desk tops are supported adequately in other manners. The superstructures permit back to back mounting of cabinets, desk tops and the like. The units thus have great versatility and adjustability for providing desk space for users.