Battle Station Operations (BSO) was not part of the Imperial Army or the Imperial Navy; instead, it was a distinct organization assigned to the DS-1 Death Star Mobile Battle Station. To ensure the Death Star functioned optimally, it was structured into eight primary divisions: engineering, logistics, maintenance, medical, personnel, security, station defenses, technical support, and numerous smaller units. The BSO personnel on the Death Star were under the ultimate command of Grand Moff Wilhuff Tarkin, who had final say on all operational decisions concerning the battle station.