Abstract: The present invention is directed toward improvements in racking systems, and in particular to a racking system which can be constructed to accommodate a variety of different sized items of equipment. The racking system includes a plurality of parallel vertical support members, each provided with a series of slots spaced apart along at least a section of the length of support member. The support members each include a locking member movable relative to the, slots between an unlocked position, in which the slots are open to allow a mounting element to be inserted in or removed from the slots, and a locked position in which mounting elements located position in which mounting elements located in any of the slots are restrained therein.