Abstract: The modular shelving system includes a shelf assembly having a plurality of elongated horizontally-extending side rails. At least some of the side rails include at least one open-ended first through slot, each first through slot extending lengthwise on a horizontally-projecting side rail strip along a common junction from a corresponding one of the side rail ends. The shelving system also includes a plurality of elongated vertically-extending corner posts to which the side rail ends are connected to form a self-standing skeletal structure. Each corner post has at least two open-ended second through slots located at a given distance in-between the corner post ends and that each extend perpendicularly from a corresponding side edge towards a common junction of the corner post. Each first through slot forms a detachable interdigitated and load-bearing engagement with a corresponding one of the second through slots to support the shelf assembly.