The International Space Station programme is tied together by a complex set of legal, political and financial agreements between the sixteen nations involved in the project, governing ownership of the various components, rights to crewing and utilization, and responsibilities for crew rotation and resupply of the International Space Station. It was conceived in 1984 by President Ronald Reagan, during the Space Station Freedom project as it was originally called.

The Commercial Crew Program (CCP) is a human spaceflight program operated by NASA, in association with American aerospace manufacturers Boeing and SpaceX. The program conducts rotations between the expeditions of the International Space Station program, transporting crews to and from the International Space Station (ISS) aboard Boeing Starliner and SpaceX Crew Dragon capsules, in the first crewed orbital spaceflights operated by private companies.