The Imperial Office of Security formed a component of the Galactic Empire's Imperial Intelligence and Security Bureau offices. These offices served Imperial Intelligence and the Imperial Security Bureau, and they were situated inside the Citadel Tower on the Outer Rim planet of Scarif. An RA-7 protocol droid, specifically 4D6-J-A7, was assigned to this office as an administrative assistant. This droid frequently encountered confidential information while working there.
During the Battle of Scarif, which occurred in 1 BBY, the Death Star superweapon, under the command of Grand Moff Wilhuff Tarkin, completely destroyed the entire tower, including the office. This destruction was ordered to prevent the Death Star plans, which were stored within the Citadel Tower's vault, from falling into the hands of the Rebellion.
The 2016 reference book Star Wars: Rogue One: The Ultimate Visual Guide, penned by Pablo Hidalgo, contained the first, though implicit, mention of the Imperial Office of Security. The 2018 reference book Star Wars: Geektionary: The Galaxy from A - Z, published by Egmont UK, was the first to explicitly identify the office by its name.