Glynn Stephen Lunney was an American NASA engineer. An employee of NASA since its creation in 1958, Lunney was a flight director during the Gemini and Apollo programs, and was on duty during historic events such as the Apollo 11 lunar ascent and the pivotal hours of the Apollo 13 crisis. At the end of the Apollo program, he became manager of the Apollo–Soyuz Test Project, the first collaboration in spaceflight between the United States and the Soviet Union. Later, he served as manager of the Space Shuttle program before leaving NASA in 1985 and later becoming a vice president of the United Space Alliance.

Flight controllers are personnel who aid space flight by working in such Mission Control Centers as NASA's Mission Control Center or ESA's European Space Operations Centre. Flight controllers work at computer consoles and use telemetry to monitor various technical aspects of a space mission in real-time. Each controller is an expert in a specific area and constantly communicates with additional experts in the "back room". The flight director, who leads the flight controllers, monitors the activities of a team of flight controllers, and has overall responsibility for success and safety.