As part of NASA's ongoing efforts to foster development of a U.S. commercial crew space transportation capability to and from low Earth orbit and the International Space Station, NASA has issued a call for industry to submit proposals for the Commercial Crew Integrated Capability Initiative.

It's expected that proposals will lead to Space Act Agreements that will help NASA and the U.S. achieve safe, reliable, and cost effective human access to space. NASA expects to make multiple awards this summer, with values ranging from $300 - $500 million.

To provide industry a better understanding of this initiative so that they may provide more comprehensive proposals, NASA plans a pre-proposal conference on Feb. 14, at the Courtyard Marriott in Cocoa Beach, Fla. Proposals are due March 23.

"President Obama is working hard to create an American economy built to last," NASA Administrator Charles Bolden said. "NASA's support of commercial innovation to reach low Earth orbit is helping to support these efforts by spurring new technological development and creating jobs and economic benefits for years to come."

NASA's announcement asks industry to propose a base period of approximately 21 months, running from award through May 2014.

The goals of the base period include completing the design of a fully integrated commercial crew transportation system, which consists of the spacecraft, launch vehicle, ground operations, and mission control.

In addition, NASA is asking for the proposals to contain optional milestones beyond the base period leading to and culminating in a crewed orbital demonstration flight.