Violent extremism continues to pose a multifaceted threat to the security of European countries. Against the growing diversification, decentralisation and de-territorialisation of this phenomenon, what policies and strategies are being implemented by decision-makers and practitioners? What role does the European Union play to prevent and counter this threat? Finally, what lessons can be drawn from the increasing securitisation of migration when it comes to policy responses to prevent and counter violent extremism? To answer these questions, the Jean Monnet Network on EU Counter-Terrorism (EUCTER) brings together scholars, experts and practitioners from several European countries to discuss the new challenges posed by the ever-evolving violent extremist threat and analyse the strategies implemented to prevent and counter it.