This introduction presents an overview of key concepts discussed in the subsequent chapters of this book. The book shares an effort to critically interrogate some aspects of counter-radicalization and also drawing on primary empirical data including from the UK's Channel Project and the Australian Resilience agenda. It points to the growing importance of this concept within terrorism studies and counter-terrorism efforts associated with what has become known as the War on Terror. The book continues with Phil Edwards' critique of the ideological inconsistency within the Prevent strategy and the strange reluctance of policymakers to consult extensive sociological studies and literature on desistance from gang violence. Such sociological and political studies of religiosity and transitions toward violence underwrite the radicalisation discourse as it is found in policy, and consolidate its conventional wisdom. It provides a blistering critique that exposes the in-built Orientalist logics of counter-radicalisation policy.