A storage apparatus for the storage of a collection of data media in the form of compact discs, CD-ROMs or DVD discs or the like in their original cases, comprising a number of individual box-like holders which can be releasably attached to each other so that the system can be simply expanded to accommodate more compact discs, CD-ROMs or DVD discs in their original cases at any desired location within the storage system. Each holder comprises a base and first and second opposing vertical side walls which hold a CD case or other case between the side walls. Each holder is provided with first and second fastening means at first and second sides respectively of the holder, adapted to permit the releasable engagement of the first fastening means of one holder with the second fastening means of an adjacent holder. The fastening means may comprise interengaging projecting portions and apertures arranged between the projecting portions, or interengaging fit male and female members. The holders may be slidably mounted on rails.