A storage system in which a base is preferably blow-molded of a lightweight polymeric material and includes a peripheral raised edge including integral sockets for receiving pivoted front and rear walls, as well as end walls and dividers. The end walls of the preferred embodiment are made of a foldable material, such that they collapse integrally with the front and rear walls, while the dividers snap-fit into the base and interlock with the front and rear walls for use. Each of the front, rear and end walls, as well as the dividers, can be folded flat for compact storage of the divider unit.