According to the assessment of the security authorities, Germany has been facing a latent threat from Islamist terrorism for years. To mitigate the associated dangers, significant financial resources are being invested in radicalization and extremism prevention. The various actors involved in Islamist prevention operate within a highly complex tension between the constitutionally guaranteed freedom of religion, the state's obligation to maintain religious and ideological neutrality, and the need for effective risk prevention. While the practice of prevention is fundamentally aware of the relevance of fundamental rights in its work, there is still a lack of transparency and concrete solutions for dealing with this tension. The author explores the constitutional framework of Islamist prevention in this book and provides insights into how Islamist prevention can be designed in accordance with the constitution.