Mine resistant ambush protected (MRAP) vehicles offer an excellent case study for investigating the current debate over the Pentagon's approach to developing and fielding irregular warfare capabilities. MRAPs first gained prominence for their ability to protect U.S. forces from improvised explosive devices (IEDs) and because the Pentagon did not deploy them en masse to Iraq until almost five years of fighting had passed. More recently, following extraordinary efforts to field more than 10,000 MRAPs quickly, the program has been criticized as wasteful and unnecessary. Secretary of Defense Robert Gates often cites the slow fielding of MRAPs as a prime example of the Pentagon's institutional resistance to investments in irregular warfare capabilities. Some irregular warfare requirements traditionally bedevil the United States-such as human intelligence-but quickly producing and fielding vehicles is something the country has done well often in the past. Moreover, the Pentagon assessed MRAPs as 400 percent more effective at protecting U.S. troops than other vehicles, and Congress was eager to pay for them. Thus, the slow fielding of the MRAPs certainly seems like prima facie evidence for the Secretary's claim that the Pentagon does not do a good job of providing irregular warfare capabilities. Yet some analysts now argue that MRAPs are not really useful for irregular warfare and are prohibitively expensive. By the time the vehicles finally flowed into the combat zone, the need for them had diminished because the insurgency and the IED problem in Iraq were on the decline. Now the Pentagon's planned procurement of MRAPs is being slashed, Congress is demanding more accountability for controlling their costs, and the MRAP program is being accused of sidetracking important future acquisition programs such as the Joint Light Tactical Vehicle and the Future Combat System. As General Barry McCaffrey, USA (Ret.), asserted, "It is the wrong vehicle, too late, to fit a threat we were actually managing." Thus, MRAP proponents, who think their delayed fielding was unconscionable, and detractors, who consider them a misguided, emotional response to casualties, both view the MRAP saga as an acquisition disaster. For incoming senior officials who are vowing acquisition reform, the MRAP experience seems to strengthen their cause. The controversial MRAPs raise two questions. First, does the MRAP experience support Secretary Gates' contention that the Pentagon is not sufficiently able to field irregular warfare capabilities? To resolve this issue, we have to determine whether MRAPs actually are a valid irregular warfare requirement, and if so, whether the Pentagon should have been better prepared to provide the kind of force protection armored vehicles like the MRAP provides. Second, what factors best explain the MRAP failure, whether that failure is determined to be the delayed fielding of MRAPs or the fact that they were fielded at all? More specifically, is the acquisition system to blame, as is commonly supposed? We conclude that MRAPs are a valid irregular warfare requirement and that the Pentagon should have been better prepared to field them, albeit not on the scale demanded by events in Iraq. We also argue that the proximate cause of the failure to quickly field MRAPs is not the Pentagon's acquisition system but rather the requirements process, reinforced by more fundamental organizational factors. These findings suggest that achieving Secretary Gates' objective of improving irregular warfare capabilities will require more extensive reforms than many realize.