GAO Report: International Space Station: Significant Challenges May Limit Onboard Research

"The ISS has been continuously staffed since 2000 and now has a six-member crew. The primary objective for the ISS through 2010 is construction, so research utilization has not been the priority. Some research has been and is being conducted as time and resources permit while the crew on board performs assembly tasks, but research will is expected to begin in earnest in 2010. NASA projects that it will utilize approximately 50 percent of the U.S. ISS research facilities for its own research, including the Human Research Program, opening the remaining facilities to U.S. ISS National Laboratory researchers."