The US National Space Policy released by the president in 2006 states that the US government should "develop space professionals." As an integral part of that endeavor, "AU-18, Space Primer," provides to the joint war fighter an unclassified resource for understanding the capabilities, organizations, and operations of space forces. This primer is a useful tool both for individuals who are not "space aware"-unacquainted with space capabilities, organizations, and operations-and for those who are "space aware," especially individuals associated with the space community, but not familiar with space capabilities, organizations, and operations outside their particular areas of expertise. It is your guide and your invitation to all the excitement and opportunity of space. Last published in 1993, this updated version of the Space Primer has been made possible by combined efforts of the Air Command and Staff College's academic year 2008 "Jointspacemindedness" and "Operational Space" research seminars, as well as select members of the academic year 2009 "Advanced Space" research seminar. Air university Press.