An automated parts supply system is disclosed for a manufacturing operation to deliver parts to individual work stations on a "just-in-time" basis. A carrier module with a supply of parts in a set of containers is placed on a computer controlled guided vehicle at a receiving station. A record of module data including the identification, quantity and location of parts in the module is supplied for use in the computer system. The vehicle is automatically controlled to move to successive work stations to deliver parts according to a predetermined schedule and in response to special interrupt requests. The system may include more than one vehicle and each vehicle may be loaded with more than one parts carrier module. An in-plant storage module may be used as a back-up supply source in conjunction with scheduled delivery of parts carrier modules at the plant receiving dock. The computer system processes initially stored delivery schedules and data and incoming real time data from the vehicles and work stations to develop the record of parts locations in the system and to generate transfer commands for controlling the vehicles.