Thomas Wade Landry (September 11, 1924 – February 12, 2000) was an American football player and coach. He is legendary for his successes as the coach of the Dallas Cowboys. He is ranked as one of the greatest and most innovative coaches in NFL history. He created many new formations and methods. He invented the now popular 4-3 defense, and the "flex defense" system made famous by the "Doomsday Defense" squads he created during his tenure with the Dallas Cowboys.