Using commercial off-the-shelf (COTS) components to build large, complex systems has become the standard way that systems are designed and implemented by government and industry. Much of the literature on COTS-based systems concedes that such systems are not suitable for mission-critical applications. However, there is considerable evidence that COTS-based systems are being used in domains where significant economic damage and even loss-of-life are possible in the event of a major system failure or compromise. Can we ever build such systems so that the risks are commensurate with those typically taken in other areas of life and commerce?