Radicalisation has been recognised in recent years in Europe as a main element in the Islamist terrorism threat conundrum. In fact, the European Union prioritised it as far back as 2005 through a European Union Strategy for Combating Radicalisation and Recruitment to Terrorism (Presidency 2005). Some criticism (COT 2008b) has been brought to these measures insofar as they do not address psychological characteristics, personal experiences and rationality. This is debatable in itself and also from the perspective of an approach to radicalisation as determined by various factors, in this case by clusters of levels of analysis: external; social; and individual. While state policies might effectively address social, economic and cultural aspects, the psychology and personal experiences of concrete individuals are not something that the state can realistically be expected to address. Furthermore, given that radicalisation is an individual and/or small group phenomenon, cluster policy mechanisms such as curbing discrimination or improving education level overall are far from certain to affect those particular individuals and/or small groups which are the cause of concern in the first place. Finally, while rationality, or better said, rational choice, appears to be a valid approach to take in understanding radicalisation, as argued in this book, it is, essentially, a different approach based on fundamentally different assumptions from those advanced in such classificatory or ‘piling’ models of radicalisation factors. Considering rationality in counterradicalisation policies could imply in its turn a rational choice radicalisation model, which is the exact opposite of the deterministic, strain concept of radicalisation at the basis of the EU strategy. Whether the EU and its Member States, who actually have the primary competence in matters of internal security, address radicalisation or not is not the main question. Partly steered by the European Commission but mainly driven by a determined assembly of ministers of the interior, European countries were relatively quick to place radicalisation on the security agenda and develop a series of initiatives, policies and action plans to combat it. European countries are ‘doing something about’ radicalisation, yet usually different things at different levels in each case and, overall, with common shortcomings having to with the initial definition of what radicalisation is, the conceptualisation of the process and its underlying mechanisms.