The rule of law enjoys considerable prominence in the ideologies of lawyers, politicians, and Parliament. Indeed, one might argue that a golden age has dawned for the rule of law, especially in the UK, the last bastion of the uncodified constitution, where it is now recognised in statute as well as judicial doctrine. Various causes may underlie these affirmations across different spheres, but one cause is surely the need for self-assurance in the face of insecurities, and one of the greatest insecurities is terrorism. It follows that the rule of law doctrine has become conspicuous in that context, where it operates both as a legal principle and a political ideology, and therefore an examination of legal doctrinal usage will form the bulk of this chapter. The analysis will reflect the hallowed writings of Albert Venn Dicey, since his three meanings of the rule of law still have greater resonance than competing versions. First, is the rule of law as legality; second, is the rule of law as equality; third, is the idea that the rule of law must underwrite fundamental individual rights and seek to repel repression. These three ideals can set the structure for this chapter in the context of terrorism and counter-terrorism. In doing so, the chapter will primarily take its examples from the UK. The survey shows that despite the evidence of many legal advances under the rule of law banner given in this chapter, it also contains, almost in equal measure, evidence of failure to live up to rule of law standards.