The Army is composed of both an Active Component (AC) and a Reserve Component (RC). The AC consists of soldiers who are in the Army as their full-time occupation. The RC consists primarily of soldiers who serve part-time but who can be ordered to full-time duty. The Army's RC is made up of both the Army National Guard (ARNG) and the United States Army Reserve (USAR). AC/RC force mix refers to the distribution of units among the active and reserve components of the armed forces.1 Debates over AC/RC mix center on whether to shift force structure between the AC and the RC and, if so, what types of units to shift. Although specific force mix recommendations can be nuanced, policy advocates generally divide between those who favor a stronger AC emphasis and those who favor a stronger RC emphasis. In the contemporary debate, those who favor a stronger RC emphasis believe that RC units can replace a portion of AC force structure while saving money. Those who favor a stronger AC emphasis believe that replacing too many or certain types of AC units with RC units is not cost-effective and could reduce the Army's ability to respond rapidly to an overseas crisis and sustain operations over time.