Abstract: An apparatus for grouping unitary dose containers which have polygonal collars receives such containers from a supply magazine and directs them by a first transfer device onto mandrels on plates carried by a rotating drum. The containers are carried by the drum to a second station where heads of a joining device join adjacent edges of collars of selected containers. Subsequently, the drum is further rotated for carrying the joined containers to another station where a second transfer device transfers the joined containers onto a receiving device.