Brigadier John Tiltman has been variously described as the greatest cryptanalyst of his time, the vest cryptanalyst ever to work for Government Communications Headquarters (CGHQ, Great Britain's counterpart to NSA), and a legend in his own time." He led the attack on numerous code and cipher systems over a dozen countries. At the same time he developed cipher systems for his own country that were unbreakable during the time they were used. He held the title of Chief Cryptographer for the Government Code and Cypher School. His career spanned two world wars, conflicts in Korea and Vietnam, and most of the Cold War.