Boeing is one half of the global duopoly in large commercial aircraft, sharing the market with Airbus behind formidable barriers: certification regimes, supplier networks and airport infrastructure built around their jets. A defense and space division supplies fighters, tankers and satellites, while a services arm monetizes the installed fleet. Aircraft are ordered years ahead, giving an enormous backlog but exposing the company to program execution, where quality and certification crises have repeatedly tested it. Boeing was founded in Seattle in 1916.