An automated order fulfillment system and automated method for fulfilling orders includes a donor-handling system having at least two donor buffers and a recipient-handling system having at least one recipient buffer. An item-handling system includes a vision system and an item manipulator. The vision system has a field of view encompassing the at least two donor receptacle buffers. A control causes the vision system to scan items in a donor receptacle at one of the donor buffers to obtain a pick list of location data of items in the scanned donor receptacle. The control causes the manipulator to pick an item from a donor receptacle at the other of the donor buffers under guidance of the vision system and place the picked item to a recipient receptacle at the at least one recipient buffer using the location data of items in that donor receptacle.