MRP and ERP system define the material requirements that are transmitted to the warehouse or distribution Centre, but they do not manage the information processes within the warehouse. This is the role of a warehouse management system (WMS), which can be designed to interface with an MRP or ERP system. As alluded to previously, product proliferation in the supply chain creates complexity in the warehouse. A warehouse system manages this complexity to trigger the right work at the right time across the operation, as illustrated in figure.