The International Space Station (ISS) Program’s greatest accomplishment is
as much a human achievement as it is a technological one—how best to plan,
coordinate, and monitor the varied activities of the Program’s many
organizations. An international partnership of space agencies provides and
operates the elements of the ISS. The principals are the space agencies of
the United States, Russia, Europe, Japan, and Canada. The ISS has been the
most politically complex space exploration program ever undertaken.