The US space agency, in an effort to send another crew change to the International Space Station, still needs to use Russian mediation. However, NASA wants to become independent of their help, so Boeing and the private SpaceX consortium are working on creating their own flight crew system.
Since NASA has canceled the shuttle program, astronauts on the International Space Station are being supplied with Russian missiles. NASA has long been trying to make it independent, but it was not possible at this time, as none of the companies had the technology to ensure safe transport of the crew into orbit.
Perhaps it will soon change, as NASA in May this year commissioned Boeing to develop a vehicle that would be suitable for crew transport to the ISS, and now did the same in SpaceX’s privately-owned consortium, Elona Muska, which by 2017 should already be ready shuttle.