The invention relates to : A liquid medication delivery device (1) for delivering an intended dose, said delivery device including means (11) for holding a cartridge (12), a cartridge (12) for holding a liquid (16) to be fully or partially injected into a body, said cartridge (12) having an outlet (121) connected to a needle at one end (123) and a moveable wall (122) at another end (124), said movable wall (122) having an inner (1221) face and an outer (1222) face, and a piston rod (18) being operable to engage and displace said movable wall (122). The object of the present invention is to reduce the overall injection time, while improving the dose accuracy for a liquid medication delivery system. The problem is solved in that the piston rod is adapted to sequentially advance the outer face of said movable wall to return to a position corresponding to the intended dose. This has the advantage of improving the performance of the delivery device. The invention may e.g. be used in pen type or doser type injection devices or in pump type infusion devices for continuous delivery of medicaton in connection with the treatment of a disease such as diabetes.