NASA's Christopher C. Kraft Jr. Mission Control Center (MCC-H, initially called Integrated Mission Control Center, or IMCC), also known by its radio callsign, Houston, is the facility at the Lyndon B. Johnson Space Center in Houston, Texas, that manages flight control for the United States human space program, currently involving astronauts aboard the International Space Station (ISS). The center is in Building 30 at the Johnson Space Center and is named after Christopher C. Kraft Jr., a NASA engineer and manager who was instrumental in establishing the agency's Mission Control operation, and was the first Flight Director.

The MCC currently houses one operational control room in Building 30 from which flight controllers command, monitor, and plan operations for the ISS. This room has many computer and data-processing resources to monitor, command and communicate with the station. The ISS control room operates continuously. A second control room in the same building, which formerly hosted the Shuttle flight control team, can be set up for ISS operations should the need arise (e.g., during repairs or hardware upgrades in the main room), and also hosts training simulations.

All Mercury–Redstone, Mercury-Atlas, the uncrewed Gemini 1 and Gemini 2, and crewed Gemini 3 missions were controlled by the Mission Control Center (called the Mercury Control Center through 1963) at Cape Canaveral Missile Test Annex, Florida. This facility was in the Engineering Support Building at the east end of Mission Control Road, about 0.5 mile (0.8 km) east of Phillips Parkway. Mercury and Gemini launches were conducted from separate blockhouses at the Cape.

The building, which was on the National Register of Historic Places, was demolished in May 2010 due to concerns about asbestos and the estimated $5 million cost of repairs after 40 years of exposure to salt air. Formerly a stop on the Kennedy Space Center Visitor Complex tours, in the late 1990s, the control room consoles were removed, refurbished, and relocated to a re-creation of the room in the Debus Center at the KSC Visitor Complex.

Located in Building 30 at the Johnson Space Center (known as the Manned Spacecraft Center until 1973), the Houston MCC was first used in June 1965 for Gemini 4.It housed two primary rooms known as Mission Operation Control Rooms (MOCR, pronounced "moh-ker"). These two rooms controlled all Gemini, Apollo, Skylab, and Space Shuttle flights up to 1996. Each consisted of a four-tier auditorium, dominated by a large map screen, which, with the exception of Apollo lunar flights, had a Mercator projection of the Earth, with locations of tracking stations, and a three-orbit "sine wave" track of the spacecraft in flight. Each MOCR tier was specialized, staffed by various controllers responsible for a specific spacecraft system.

MOCR 1, housed on the second floor of Building 30, was used for Apollo 5, Apollo 7, the Skylab and the Apollo-Soyuz Test Project (Saturn IB) missions.

MOCR 2 was used for all other Gemini and Apollo (Saturn V) flights (except Gemini 3) and was located on the third floor. As the flight control room for Apollo 11, the first crewed Moon landing, MOCR 2 was designated a National Historic Landmark in 1985. It was last used in 1992 as the flight control room for STS-53 and was subsequently converted back almost entirely to its Apollo-era configuration and preserved for historical purposes. Together with several support wings, it is now listed in the National Register of Historic Places as the "Apollo Mission Control Center". In January 2018, the first set of consoles in MOCR 2 were removed and sent to the Kansas Cosmosphere for archival cleaning, refurbishment, and restoration to Apollo-era configuration, for eventual display back in the control room. On July 1, 2019, the newly restored Apollo-era Mission Control was reopened to the public, after a two-year long effort to restore the room to its configuration as seen during the Apollo Moon landings. Period-appropriate accents were acquired, from cigarette packs and ashtrays to wallpaper and carpeting. The room is accessible via the tram tour at the nearby Space Center Houston visitors' center, but only from behind the glass in the restored Visitor's Gallery viewing room.

In July 2010, air to ground voice recordings and film footage shot in Mission Control during the Apollo 11 powered descent and landing was re-synchronized and released for the first time. This audio was used in creating an audio-visual presentation for the 2019 Mission Control update.