An infusion device for making beverages using cartridges, such as capsules or pods, comprises an openable infusion unit (3) comprising at least one part (4) able to move between a home position and an operating position, a first standby zone (8) for a cartridge (2) being formed when the mobile part (4) is in the home position, first retaining means for a cartridge (2) in the first standby zone (8), a motor (13) for moving the mobile part (4), means for expelling the cartridge (2) from the unit (3), and at least one device (1) operation check and control unit (35); there are also second retaining means (36) positioned between a cartridge insertion section (34) and the first standby zone (8), to selectively retain a cartridge (2) at a second standby zone (37), the check and control unit (35) being programmed to cause the dispensing of two beverages, one after another, using two cartridges.