This book provides a homogeneous theoretical framework on radicalization and de-radicalization based on previous literature and several new original elements that are the product of the research of the three authors; this framework is then applied to three different historical scenarios. The aim of the book is to provide a complete and comprehensive framework to understand the phenomenon of jihadist radicalization and deradicalization. It is based on a wide selection of multidisciplinary literatures which have treated the topic from different perspectives in order to depict a picture as complete as possible. Such a multidisciplinary approach is enriched by original elements derived from the authors' work and empirical research. This theoretical framework is applied to three different case-studies: the case of Hamas in Palestine, the case of the Islamic Group in Egypt and the cases of Ennahdha and Ansar al-Sharia in Tunisia. All these groups showed rather different paths of radicalization and only two of them deradicalized. Through the analysis of their historical paths, the authors elicit the common mechanisms and dynamics that, according to the different contexts, led them to different or similar developments. This book will be of much interest to students of deradicalisation, counter-terrorism, Middle Eastern studies and International Relations.