A device stores, mixes, and applies polymethylmethacrylate bone cement. The device comprises a first container for a first pasty component of the bone cement, a dispensing plunger arranged in the first container such that it can be shifted and serves for pressing the content of the first container out of a dispensing opening, a mixing facility for mixing the content of the first container, whereby the mixing facility is arranged in the first container and the mixing facility can be moved in the first container from outside for mixing, and at least one second container for at least one second component of the bone cement is arranged in or on said first container. The second container can be opened, such that the contents of the first container and second container can be mixed with each other in the first container, whereby at least a boundary surface of the first container is formed by a mobile volume compensation element.