This chapter describes the diverse considerations governments should take into account as they seek to build or improve a national counterterrorism capability. For the purposes of this discussion, conducting a successful hostage rescue operation will serve as the benchmark for a competent counterterrorism capability. Although terrorists armed with a weapon of mass destruction and seeking to leverage that weapon (or weapons) to blackmail a government present perhaps the most difo cult decision for politicians as they consider the employment of their counterterrorism forces, we can be thankful that such a scenario has not yet occurred. Rather than address such a theoretical challenge, this chapter will focus on counter terror hostage rescue operations. Recent history is replete with many case studies of both successes and failures in these operations, from which lessons learned may be drawn. These also serve to highlight the key challenges for the three elements involved in any hostage rescue decision; the counterterrorism force, the intelligence structures supporting the rescue, and the politicians who must decide whether or not to launch the operation. Despite a decrease in the appeal of hostage-taking operations in apparent favor of suicide body, car, and truck bombs, terrorists still can get major mileage out of hostage taking. The most recent example is the attacks on luxury hotels by Lashkar e-Tayyiba– trained Muslim extremists in Mumbai during November 2008. To have decent odds for the conduct of a successful hostage rescue, there are three components of any government that must come together to form an alliance of shared capabilities, risk analysis, and political resolve. First, the government beset with a hostage-taking situation must possess a trained hostage rescue force—the hammer. Second, an intelligence capability must be able to provide adequate details about the hostage crisis to enable a reasonable chance of a successful rescue—the eyes. Third, political leaders must have cono dence in both the rescue force and the intelligence underpinning the operation. Politicians, the brain, must muster the political will to close the crisis by launching an operation—and suffer the consequences, good or bad. I refer to these three components—hammer, eyes, brain—as the “Iron Triangle” of counterterrorism decision making. In most governments, the three components (where they exist) live in separate worlds, that is, separate ministries, different values, divergent concepts of risk and degrees of risk aversion, different skill sets, different understandings of the political environment.