Abstract: A conveyor conveys boxes that are empty and boxes that are filled with articles in a horizontal plane past an article handling machine where articles of a first type are removed from some boxes and articles of a second type are inserted in empty boxes. The machine runs concurrently with the box conveyor in one direction so boxes from which the articles of the first type are conveyed beyond the machine and empty boxes in which articles of the second type are inserted are also conveyed from the machine in the same direction. The article handling machine has heads that are constrained to orbit in a generally circular path and the heads have grippers on them which are controllable to grip and release groups of articles at consecutive working stations along the orbital path of the heads.