Since the retirement of the Space Shuttle Program in July 2011, the United States has lacked a domestic capability to transport crew and -- until recently -- cargo to and from the International Space Station (ISS or Station). Consequently, NASA has been relying on the Russian Federal Space Agency (Roscosmos) for crew transportation. In anticipation of the Shuttle's retirement, Congress and the President directed NASA to foster the commercial spaceflight industry as a means of developing domestic cargo and crew transportation capabilities to the Station. In November 2005, NASA created the Commercial Crew and Cargo Program Office and in 2011, activated a separate Commercial Crew Program Office to reflect the increased funding and priority for commercial crew. In June 2013, the Office of Inspector General (OIG) issued a report examining NASA's efforts to foster a commercial market for cargo resupply missions to the ISS. The report discusses NASA's funding over the past 7 years of SpaceX and Orbital to further development of spaceflight capabilities and, on a separate track, the Agency's contracts with the companies for a combined 20 cargo resupply missions to the ISS. As a complement to that report, this book examines NASA's efforts to pursue commercial crew capabilities.