This book offers an in-depth and yet-unexplored analysis of the evolution and actions of Moroccan Islamist association Justice and Spirituality (al-Adl wa-l-Ihsane). By examining its mobilisation structure, the book enhances the understanding of Islamism as an oppositional force in non-democratic regimes, with a particular focus on Morocco. Contrary to the common premises of inclusion moderation theory, al-Adl wa-l-Ihsane has undergone a politicisation process but rejects political inclusion; it promotes street mobilisation but refuses to resort to violence. Despite its illegal status and disregard for the regime's red lines, al-Adl wa-l-Ihsane remains highly relevant as an anti-establishment actor. This book fills a significant gap in knowledge about al-Adl wa-l-Ihsane. It further broadens the understanding of inclusion moderation theory by introducing novel explanatory factors for al-Adl wa-l-Ihsane's evolution and strategies, such as responses to shifts in opportunity structures and the impact of internal dynamics and learning mechanisms.