This paper defines and analyses the most important issues concerning decision making about human-induced insecurities such as terrorism and organized crime from the perspective of a policymaker. By means of modeling the policymakers trade-off between the effectiveness and costs of policy measures targeted at reducing the threat of terrorism, we aim at helping to understand the role economic research can take to enable efficient decisionmaking in thecontext of human-induced insecurities in general and terrorism in particular.