This talks examines the creation of the Dowding System. This was a revolutionary air defence network that provided early warning of air attacks and played a pivotal role in Britain’s victory during the Battle of Britain in 1940, saving the nation from Operation Sealion, the planned invasion of England in 1940, and ultimate defeat. Despite its significance, the Dowding System’s development has been somewhat neglected by many historians. Most accounts of the battle focus heavily on the advances in radar technology, paying little attention to the broader Dowding System. The system seamlessly integrated radar with physical observations and hierarchical reporting to form the backbone of Britain’s air defences.