An apparatus for assembling an electrical plug connector on a first cable end and/or on a second cable end of an electrical cable which has one or more inner conductors. The apparatus has at least one module group with at least two processing modules for processing the cable. The apparatus furthermore has a feed device for feeding the cable end along a feed direction (X) to a processing station (B) in the module group. The module group has a module transport device for feeding in each case one of the processing modules of the module group to the processing station (B). The feed device is configured to remove the cable end from the module group counter to the feed direction (X) after the processing.