NASA's Christopher C. Kraft, Jr. Mission Control Center (MCC-H), also known by its radio callsign, Houston, at the Lyndon B. Johnson Space Center in Houston, Texas, manages all American human space flight; including US portions of the International Space Station (ISS). The center is named after Christopher C. Kraft, Jr, a retired NASA engineer and manager who was instrumental in establishing the agency's Mission Control operation.

The MCC currently houses one operational control room, from which flight controllers coordinate and monitor the ISS. These rooms have many computer and data-processing resources to monitor, command and communicate with spacecraft. From the moment a space shuttle cleared its launch tower in Florida until it landed on Earth, it was in the hands of Mission Control. When a shuttle mission was underway, its control room was staffed around the clock, usually in three shifts. The ISS control room operates continuously, but with fewer controllers.

Because Houston is a hurricane-sensitive area, NASA has basic back-up facilities at the Kennedy Space Center as well as a location at the Backup Control Center Huntsville Operations Support Center (BCC-HOSC) at Marshall Space Flight Center for ISS operations. (Unmanned US civilian satellites are controlled from the Goddard Space Flight Center in Maryland, while California's Jet Propulsion Laboratory manages unmanned US space probes.)