The work of the RAF’s 100 Group remains one of the least known aspects of the 1939-45 war. Even less has been written about the specifics of day-to-day electronic warfare operations and the countermeasures employed. This book, the result of many years meticulous research by Squadron Leader Richard Forder RAF (Ret’d) redresses the balance by focussing on one the heavy units, 223, and its sister units at RAF Oulton, Norfolk.Equipped with former USAAF Liberators, they operated from August 1944 to the end of the European war, with a primary role of protecting Bomber Command Main Force ops by radio and radar countermeasures against German defenses. By analyzing original documents and recording first hand accounts from both sides of the conflict, including those of Main Force personnel, Forder and Bond present a complete, detailed and valuable picture of the secret and vital activities of the special operatives, and their effect on German defenses.