Countering violent extremism (CVE) is a widely used and defined term. From a practitioner’s perspective, it works on three levels: prevention of radicalization, intervention with individuals in danger of radicalization, and de-radicalization. The European Union pursues a holistic approach, which includes transnational collaboration and eliminating possible root causes of radicalization. The focus is not exclusively on national security concerns but also on prevention, de-radicalization, and rehabilitation. European states have developed a variety of CVE strategies, some of which are perceived as centrally controlled, while others are characterized by participative and cooperative structures. At both the European and national levels, collaborative approaches that encompass incorporation of civil society organizations and governmental programs are seen as the most effective in CVE.