From their inception during the Cold War through to operations in Afghanistan and beyond, Special Observers from 4/73 (Sphinx) Special Observation Post Battery, Royal Artillery and its antecedent units, have provided a unique and specialist capability to the British Army. The unit, and its capability, is discreet by its very nature and in line with its unit motto Lateo, which means to 'Remain Hidden'. In 1982, amidst the tension of the Cold War, the unit was established with a distinctive mission - to operate covertly behind enemy lines, awaiting the passage of Warsaw Pact units, before engaging follow-on forces. These elite soldiers, comprised of specially selected teams of six men, would take refuge in underground shelters, emerging to deploy to observation posts armed with the firepower of the British army. The tasks of this specialist unit, which is part of the Royal Artillery's 1st Intelligence Surveillance and Reconnaissance Brigade, include directing artillery fire and strikes from attack aircraft and precision missiles and providing crucial battlefield intelligence on enemy positions, movements, strength and morale. The battery has also deployed as Surveillance and Target Acquisition (STA) Patrols which operate far from the main force, sometimes deep behind enemy lines. Members of the battery are expected to be able to remain hidden for up to a week without the enemy being aware of their presence. The 1980s and 1990s saw numerous deployments to Northern Ireland and Balkans. As the world changed following the terrorist attacks on 9/11 so did the unit, finding itself deployed to Iraq and Afghanistan numerous times. Written by a former Special Observer and Infantry Officer troop commander with contributions from across the military, including UK Special Forces, Special Observers of all ranks, and British Army generals, this is the first time the world has been provided with a glimpse into this highly secret unit.