As terrorism and radicalisation become ever more complex and multifaceted, this study goes beyond a mere cause and effect analysis and looks at the problem from different angles, including radicalisation in schools, universities and mosques; its geostrategic aspects; the nature of online extremist narratives; the nexus between the extreme right and jihadist radicalisation and examples of effective countering violent extremism (CVE) measures. The one thing all authors agree on is that, in order to address radicalisation successfully and keep EU citizens (and others around the world) safe from further terrorist attacks, intensified cooperation and intelligence-sharing between and among member states and between the EU and its partners, is key. However, this will be insufficient in the absence of a strategy vis-à-vis addressing one of the root-causes of radicalisation, namely the ideology driven by an extremist interpretation of Islam. Therefore, EU member states need to offer marginalised and disillusioned youths vulnerable to radicalisation a better alternative and promote a positive counter-narrative based on its own founding principles of freedom and democracy.