Many counterterrorism e"orts in last decades, and especially since 9/11, have been plagued with doubts as to whether or not they actually make us safer. Unfortunately, the terrorism research that is needed to better plan and evaluate counterterrorism e"orts has su"ered from both a lack of su&cient rigour and lack of in%uence on policy-making. !is article reviews the state of terrorism research and evidence-based practice in counterterrorism, and the challenges to both. A framework is proposed for the kind of research that needs to be conducted in order to develop evidence-based counterterrorism programs as well as the subsequent evaluative research on existing programs as part of a wider quality improvement program. !e argument is made that there is a need for a concrete infrastructure of evidence-based practice and quality improvement in counterterrorism to ensure the best outcomes for national security. !e components of a full spectrum quality improvement program in counterterrorism are described. Insights are garnered from the #eld of medicine, which has recently delved full force into evidence-based practice and quality improvement.