The UK entered the era of Jihadist terrorism with a poor understanding of the nature of the newly emerging threat, a siloed approach to inter-agency co-operation, fragmented intelligence structures and a policy approach ill-suited to the threat. The following 18 years saw considerable success in disrupting many terrorist attacks, the arrest and conviction of hundreds of people for terrorism offences, the development of a cross sector multi-agency counter-terrorism strategy – CONTEST, the creation of an effective intelligence sharing organisation (JTAC) and a dramatic expansion in the size and capabilities of the key CT bodies. Strategically, any belief that CONTEST has succeeded is a narrow reading of its stated aim, since the threat of terrorism can hardly be said to have reduced and public concerns about terrorism remain high. The UK has not adopted wider emergency measures such as those seen in France, but it has stretched any definition of normality through a series of significant changes in how the state is secured. The CONTEST review of 2018 disappointingly did not provide clarity on how the operational successes of almost 20 years of counter-terrorism can be matched strategically. It is to be hoped that future policy developments will quickly provide this guidance.