The Officio Logisticarum, also known as "Guilliman's Hand," was an agency of the Imperium of Mankind created on the order of the Lord Commander of the Imperium Roboute Guilliman during the Indomitus Crusade.
The Officio Logisticarum was an attempt by Guilliman to go around the massive and ponderous Imperial bureaucracy of the Adeptus Administratum in the late 41st Millennium so as to rapidly build up the materiel needed to launch and resupply the galaxy-wide Indomitus Crusade.
To bring the Indomitus Crusade to fruition, the Ultramarines' resurrected Primarch chose to bypass the established Imperial bureaucracy entirely. Guilliman created his own elite cadre of facilitators whose role was to ensure proper supply and marshalling of every single starship and soldier for the crusade.
Named as the Officio Logisticarum, but known throughout the crusade fleets as "Guilliman's Hand," this body was millions of souls strong, its members drawn from the best that Terra's Administratum and Departmento Munitorum bureaucracies had to offer, and still it was barely equal to the task.
Early in the Indomitus Crusade, the Primarch Roboute Guilliman issued the so-called "Borachae Decree" which declared that not only would the Officio Logisticarum be empowered to request military support and protection up to and including assigning tithed Astra Militarum regiments to their own protection, but they would also be furnished with planetary hub-fortresses from which to supply, support, and archive the actions of the Indomitus Crusade fleets.
- White Dwarf 35 (July 2019), "Indomitus Crusade Fleets," pp. 40-45
- White Dwarf 39 (November 2019), "Dawn of the Era Indomitus," pp. 46-51