Since the earliest days of spaceflight, substantial concern has
been expressed regarding the physical needs of astronauts,
including any biological damage that might result from exposure
to radiation or from reduction in gravitational forces. In
contrast, relatively little concern has been directed towards
people's psychological and social adjustment to space. At one
time this difference in emphasis was justified. The Mercury,
Gemini, and Apollo flights were measured in hours and days and
it could be reasonably assumed that astronauts would be able to
withstand certain deprivations for these brief periods. The
longer flights of Skylab presented a different picture. Early in
the development of Skylab, it was recognized that steps would
have to be taken to accommodate a wider variety of human needs.
However, the needs that were addressed remained narrowly defined
and centered primarily on habitability considerations. We are
now at the point in the development of spaceflight where the
range of psychological and