Under the Bush administration, the Constellation Program included plans for retiring the Shuttle program and replacing it with the capability for spaceflight beyond low Earth orbit. In the 2011 United States federal budget, the Obama administration cancelled Constellation for being over budget and behind schedule while not innovating and investing in critical new technologies. For beyond low earth orbit human spaceflight NASA is developing the Orion spacecraft to be launched by the Space Launch System. Under the Commercial Crew Development plan, NASA will rely on transportation services provided by the private sector to reach low earth orbit, such as Space X's Falcon 9/Dragon V2, Sierra Nevada Corporation's Dream Chaser, or Boeing's CST-100. The period between the retirement of the shuttle in 2011 and the initial operational capability of new systems in 2017, similar to the gap between the end of Apollo in 1975 and the first space shuttle flight in 1981, is referred to by a presidential Blue Ribbon Committee as the U.S. human spaceflight gap.

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