Abstract: A modular conveyor system for use in a warehouse having a plurality of elongated, multi-level order selection racks includes a plurality of powered picking conveyors supported in vertically spaced superimposed relationship, a plurality of accumulator conveyors supported above the picking conveyors in a common horizontal plane, a merge conveyor sequentially receiving a batch of articles from the accumulator conveyors and discharging the articles onto a sortation conveyor. The sortation conveyor includes a plurality of article diverters for automatically diverting predetermined articles from the batch onto a plurality of discharge conveyors. A palletizer station positioned adjacent each of the discharge conveyors includes a storage area for a plurality of pallets and a lift to transfer a loaded pallet to a run out conveyor which permits the pallet to be transferred to a truckloading area.