Abstract: A universal media module for use with a data storage library system containing at least one storage array for holding at least one universal media module. The universal media module is removable from the storage array. The universal media module is capable of containing a variety of media cartridges of various sizes, and the media cartridges may vary in size in at least one dimension. The universal media module has a housing having a top wall, bottom wall, side walls, rear wall, and an open front; a mechanism for removably attaching the housing to the data storage library system; and at least one media storage slot formed by supporting members engaging the side walls of the housing and extending along the side walls from the open front to the rear wall.