While terrorism is one of the most prominent security threats in the Western world, there is surprisingly little research that addresses the effectiveness of the instruments that are used to fight it. In my doctoral dissertation The science of fighting terrorism, which I wrote at Leiden University, I tried to fill this gap by demonstrating that there is a link between the nature of a terrorist threat and the effects of the measures that are applied against it. On the basis of a series of in-depth case studies, ranging from the Provisional IRA and the RAF to modern-day jihadist terrorism in the UK and the Netherlands, I showed that different terrorist threats require different countermeasures. You can find an English summary here and a more extensive Dutch summary here. The full dissertation is available here.