The function of determining the need to replenish inventory at distribution centers. A time-phased order point approach is used, based on regional forecasts, customer orders, and inventories. The planned orders at the distribution center level are “exploded” via MRP logic to become gross requirements on the supplying source. In the case of multi-level distribution networks, this explosion process can continue down through the various levels of regional distribution center, factory warehouse, etc. and become input to the master production schedule. Demand on the supplying source(s) is recognized as dependent, and standard MRP logic applies.