Expedition 64 was the 64th long-duration expedition to the International Space Station (ISS), that began on 21 October 2020 with the undocking and departure of Soyuz MS-16. The Expedition started with the three crew members launched onboard Soyuz MS-17 and reached its full complement with the arrival of SpaceX Crew-1, the first operational flight of NASA's Commercial Crew Program (CCP). As Crew-1 consists of a crew of four instead of three like the Soyuz, Expedition 64 marks the beginning of operations for crews of seven on the ISS. In the final weeks of the mission, Soyuz MS-18 and its three cosmonaut crew joined the mission. The expedition ended on 16 April 2021 with the departure of Soyuz MS-17.