Abstract: A shopping cart scanning system is disclosed comprised of first and second photoelectric devices situated in a check-out counter and respectively located at the entrance and exit portion of a scanning field. The photoelectric devices both operate in a retro-reflective mode and operatively cooperate with a reflective strip that is attached to the shopping cart. The photoelectric device, and their associated circuits, are arranged to detect the presence or absence of packages in the lower tray of the shopping cart as the shopping cart moves through a check-out counter.