After serving briefly as the Chief of Staff for the Air Force Systems Command at Andrews Air Force Base, Maryland, Allen was appointed in March 1973 as a deputy to the Director of Central Intelligence for the Intelligence Community in Washington, D.C. In August 1973, Allen became the Director of the National Security Agency (NSA) and the Chief of the Central Security Service at Fort George G. Meade, Maryland. Allen's tenure as the NSA director was noteworthy in that he became the first director to ever testify publicly before Congress. In August 1977, he was named Commander of Air Force Systems Command.