STS-213's mission was to deliver the second Soyuz/Progress Docking Module, which will be used exclusively for docking of manned vehicles (the first module being used primarily for unmanned supply vehicles, and the initial arrival of Soyuz vehicles). This new module will allow the station to increase the station's permanent crew from 3, to 6, and eventually to its full capacity of 10 when the European Crew Transfer Vehicle begins to arrive.