 We do not negotiate with terrorists. A favorite phrase of world leaders and Hollywood directors alike. Our leaders repeat this phrase so often and with such conviction that negotiation has become a dirty word. Negotiations are seen to be a last resort, conducted in secret and publicly denied. The cost of terrorism is unacceptable. But what about the human cost of countering terrorism? Three-year-old Alan Curdie lost his life fleeing from terrorism-related violence. Now, he wasn't just fleeing from Islamic State, but also from the military responses to terrorism that had plagued his short life. Almost two decades on, and not only is there no end in sight to the war on terror, but it has caused the biggest humanitarian crisis of our time. The status quo simply isn't working. There is a secret weapon in the counter-terrorism arsenal. Negotiating or communicating with terrorists significantly reduces destruction, displacement and death. Between 1968 and 2006, negotiations helped almost half of groups engaged in acts of terrorism to stop using violence. In contrast, just over 5% ended due to military action. As a diplomatic studies scholar, my research increases this success rate by optimising how states approach negotiations as a counter-terrorism tool. Now, every conflict situation is different, with no two takes being the same. As such, scholars disagree on the relative importance of factors that affect negotiations with terrorists. For example, one school believes that negotiations with the Irish Republican Army succeeded because they involved all willing actors. Another contends that it was due to addressing core interests and grievances, while others still attribute it to everyone suffering equally. People can't agree on what makes negotiations work. In light of this, I look at negotiating holistically. By comparing factors simultaneously, I am able to identify which factors are necessary or sufficient for negotiating with terrorists, equipping leaders with a screenplay for weather and how to engage in negotiations. Alan Curdie reminded the world of the costs of fighting fire with fire. When negotiations already enjoy a 600% better-tracked record than military action, can we really afford to not negotiate with terrorists?