Since 1997, RAND has studied options for configuring an Agile Combat Support (ACS) system that would enable the achievement of Air and Space Expeditionary Force (AEF) goals. Operation Iraqi Freedom (OIF) offered an opportunity to examine the implementation of new ACS concepts in a wartime environment. In 2000, Project AIR FORCE helped evaluate combat support lessons from Joint Task Force Noble Anvil (JTF NA), the U.S. component of Operation Allied Force, in Serbia. In 2002, Project AIR FORCE evaluated combat support lessons from Operation Enduring Freedom (OEF), in Afghanistan. Some of the concepts and lessons learned from JTF NA and OEF were implemented in supporting OIF. Supporting Air and Space Expeditionary Forces: Lessons from Operation Iraqi Freedom presents an analysis of combat support experiences associated with Operation Iraqi Freedom, the war in Iraq, and compares these experiences with those associated with JTF NA, in Serbia, and the first 100 days of OEF. The analysis offered an opportunity to compare findings and implications from JTF NA, OEF, and OIF. Its objectives were to indicate how combat support performed in the OIF scenario; examine how ACS concepts were implemented in OIF; and compare JTF NA, OEF, and OIF experiences to determine similarities and applicability of lessons across experiences and to determine whether some experiences are unique to particular scenarios. The report focuses on experiences from OIF and what those experiences imply for combat support system design to ensure that AEF goals can be achieved. Combat support planning and execution (CSC2) processes and command and control organizational alignments have improved since JTF NA and OEF. The implementation of pieces of the future, or TO-BE, CSC2 operational architecture aided in this development, although integrating deliberate planning processes and crisis planning activities requires more work. As well, austere forward operation locations (FOLs) and an immature theater infrast