The Strategic Command
The strategic command of the Imperial Guard is provided by the Departmento Munitorium of the Administratum. This department of the Adeptus Terra forms the general staff of the Imperial Guard responsible for munitions, supply, recruitment, training, transportation and all aspects of the Imperial Guard establishment.
The chief of strategic staff of the Departmento Munitorium is the Lord Commander Militant of the Imperial Guard, a powerful official and often one of the High Lords of Terra. Within each of the four outlying Segmentae of the Imperium there is a separate strategic command base alongside the fleet bases at Cypra Mundi, Bakka, Kar Duniash and Hydraphur. The fifth base is on Earth in the Segmentum Solar. Each of these has its own strategic command staff and reserves. The Lord Commander of each Segmentae is in charge of all military operations within his area, an awesome responsibility indeed.
In any active war zone there are hundreds of senior commanders with thousands of personal staff. In addition there are tens of thousands of scribes, observers and organisational officers of the Departmento Munitorium. Indeed, for every fighting man there stands behind him a virtual army of bureaucrats and support personnel whose efforts keep the armies going. However, within the Imperial Guard itself there is a complex system of high ranking officers responsible for the strategic and grand tactical military operations.
These staff officers rarely take part in the fighting. Occasionally an Imperial Guard general might find himself embroiled in the action, but this is likely to be by accident rather than by intent. The only staff officers who regularly fight at the front are Commissars. (From Codex: Imperial Guard.)