The paper will explore the theoretical background and state of the research in regard to De-radicalization and Disengagement Programs (DDPs i.e. ‘Exit Programs’) as counter-terrorism and prevention tools against violent radicalization leading to terrorism. Introducing the theory of a ‘counter-terrorism network’ working on three social scales (macro-, meso-, and micro-social) and three impact levels (prevention, repression, intervention) the paper will explore in detail how exactly de-radicalization programs can yield a high impact on radical milieus and become a cornerstone of a society's resilience. In addition the paper will give a broad introduction to de-radicalization studies and an overview of relevant research in the field. Case studies and insights from two of the world's most successful programs will show how the theory might work in practice: EXIT-Germany (counselling highly radicalized individuals wanting to leave the German extreme right-wing scene) and HAYAT (a German family counselling program for the relatives of Jihadists and Foreign Fighters, as well as of individuals on the path of non-violent radicalization). Both programs have been running for some time (EXIT since 2000 and HAYAT since 2011) and have yielded an enormous amount of primary data on the practice of de-radicalization and the impact these programs can have on highly radical milieus. As both programs were initially designed as non-state actor counter-terrorism programs the paper will compare the practical insights derived from these two programs in light of the ‘counter-terrorism network’ theory. The paper will conclude with a summarizing theory of deradicalization programs as counter-terrorism and prevention tools and how these programs can be set-up effectively in order to achieve this end.