International Space Station Alpha, which has been in operation since December 2000, is scheduled for completion in 2006. "Alpha," as it is nicknamed, is becoming the site of extensive human physiological research, life and physical science investigations, and commercial work that will continue for at least ten more years. Circling Earth once every 90 minutes, and at an altitude roughly the same as the distance from Washington, D.C. to New York City, Alpha is the latest and most evolved orbital space station.^* But almost certainly there will be others. What will they be like? And how might they be used?

As the work at Alpha returns knowledge and stirs public interest, national space agencies, scientists, and business people are considering beneficial activities that could be conducted onboard future stations in orbit. Even the armed forces have considered the use of crewed space...