The paper reviews a present state of the art in magnetron sputtering of alloy films. It shows that a mixing process, i.e. the addition of a second element into a base, one element film is, together with ion bombardment, the second dominant process which can be used to control film structure. It describes general properties of one element films, binary metal alloy films and films made of nitrides of binary metal alloys. Special attention is paid to the formation of the nanocrystaline and nanocomposite films with a grain size of about 10 nm and smaller, and of the high-temperature phases at low temperatures close to room temperature. The alloy and alloy-based films with nanocrystalline structure represent, due to their novel structure and new physical properties, a new generation of materials.