This volume is the first practical handbook that precisely analyzes the existing issues and outlines the prerequisites that must be met for effective radicalization prevention. Additionally, it provides an overview of the Western European prevention landscape, along with pioneering concepts and initiatives. In the past three years alone, more than 5,000 mostly young people have traveled from Western Europe to the war zones of Syria and Iraq to participate in the establishment of the so-called Islamic State. Given this very high number, radicalization prevention is becoming increasingly important in all areas of societal action - particularly in communities, youth services, and schools. Radicalization prevention is still a very young discipline in Germany, which is emerging in practical fields.