The disclosure relates to a slat alternation apparatus in a machine for the manufacture of venetian blinds and the like, for optional alternation of slat belts (2-6) of different colors during the manufacture of a venetian blind, a magazine (1) with a number of different slat belts (2-6) being laterally shiftable at the infeed end of the machine, for positioning of the desired slat belt (2-6) in a position for infeed into the machine.