A technology primarily used for “eaches” order picking that can drive significant gains in productivity by its “hands free” nature. In a typical operation, a picker will scan a carton or tote ID barcode. That action will light a numeric display in a group of locations, indicating the specific location to pick from for each location and how many items are needed. The picker moves to the first location, places the indicated quantity in the tote/carton, and then pushes a button to indicate that pick is complete. He or she then repeats the process until all the picks in a zone are complete. Lights can also be placed on a pick cart, turning it into a “smart cart.” Pick-to-Light is closely related to the concept of Put-to-Light.