Abstract: A shelf system for the storage and filing of objects is provided. The system includes at least one shelf unit having a quadrilateral cross-sectional configuration. Vertical longitudinal posts are disposed at corners of the shelf unit. Horizontal crosspieces are disposable between two front ones of the posts. The crosspieces are provided with vertically and horizontally spaced apart, downwardly directed pairs of hooks. The posts are provided with recesses for receiving the hooks. Supporting boards are provided and each have a downwardly directed front flap that is adapted to be firmly wedged between a crosspiece and the posts that receive them to prevent lifting of the supporting boards.