Peace operations (POs) are arguably the military operations other than war most likely to stress the U.S. Army's ability to maintain combat readiness. POs require: a higher ratio of combat support/combat service support units and special operations forces relative to combat arms units than do major theater wars (MTWs); smaller, more tailored deployments; training for some new tasks and, more important, for a more restrictive and sensitive operational environment; and readier access to--and more of--some kinds of equipment (such as crowd and riot-control gear, nonlethal weapons, and vehicles). At a time when the Army is shrinking, changing its posture, and participating in a rising number of both exercises and operational deployments, its challenge is to both maintain MTW readiness (its primary mission) and meet the very different requirements of POs. As long as MTWs remain the national priority--and thus the Army's--the Army can make some marginal changes to force structure, training, and doctrine that will help improve PO performance while also mitigating the effects of PO deployments on MTW readiness. If POs become a higher priority, and resources remain constrained, the Army will have to trade off some MTW capabilities to better meet PO requirements. These challenges must also be viewed in light of existing Army problems (such as maintaining units at levels below normal strength and overestimating the readiness of the reserve component), which transcend POs but are severely exacerbated by PO deployments.