The invention relates to a mixing device for mixing PMMA bone cement from amonomer liquid and a cement powder (9), the mixing device comprising at leastonecartridge (6) having an evacuable interior for mixing of the bone cement (96),a mixingdevice (10) for mixing the content in the interior of the at least onecartridge (6), which isarranged movably in the interior, a receptacle (2) for receiving a separatecontainer (54)containing the monomer liquid or comprising an integrated container containingthemonomer liquid, an opening device (5), which is arranged in the region of thereceptacle(2) in a manner movable relative to the receptacle (2) so that, by moving theopeningdevice (5), a separate container (54) arranged in the receptacle (2) isopenable bymeans of the opening device (5), or the opening device (5) is arranged in theregion ofthe integrated container in a manner movable relative to the integratedcontainer sothat, by moving the opening device (5), the integrated container is openableby meansof the opening device (5), a pressure pump (3), in which a movable plunger(30) forconveying a liquid is arranged and delimits a pump chamber (28) of thepressure pump(3) and a connection line (26), which connects the interior of the at leastone cartridge(6) to the pump chamber (28) of the pressure pump (3), wherein the mixingdevicecomprises an operating element (4) that is operatable from outside, whereinthe plunger(30) in the pressure pump (3) is movable manually by means of the operatingelement(4), and wherein the opening device (5) is to be moved relative to thereceptacle (2) orrelative to the integrated container by means of the same operating element(4), and themixing device (10) in the interior of the cartridge (6) is movable by means ofthe sameoperating element (4) in order to mix the content in the interior of thecartridge (6).The invention also relates to a method for mixing PMMA
