Radicalization is a well-written, pedagogical, and thoroughly researched book about how extreme religious and political organizations work to make people dependent on them. The book specifically discusses the Islamic State, Jehovah’s Witnesses, the Moon Movement, the Pentecostal Church, the Church of Scientology, and the Nordic Resistance Movement.

There are also sectarian tendencies in organizations such as companies, sports clubs, nonprofit associations, criminal gangs, and motorcycle clubs. The book provides a comprehensive review of sectarian ideologies, language, and leadership. It describes the radicalization process—how people are recruited, shaped, and live their lives within sects and sect-like organizations.

Detailed case studies of four individuals are included. The author offers practical advice to professionals in education, social services, psychiatry, law enforcement, and corrections on warning signs, intervention, how to motivate individuals to leave, and how to support people in radical environments.

Finally, the book presents an overview and discussion on working with defectors, including instructions and advice for practitioners as well as effective treatment plans.

Håkan Järvå was a member of the Church of Scientology for fourteen years. After leaving, he trained as a psychologist and has worked with individuals leaving sects and radicalized organizations. He has previously compiled the anthology Sektsjuka (2009) and co-authored Influence and Manipulation (2013) with Peter Dahlgren.

For anyone interested in understanding how ordinary people can end up in radical environments and why it is so difficult to leave them, this book is a real gem. There is so much one didn’t know before that some sections may need to be read multiple times.

For me, it was somewhat unsettling to realize that everything I would instinctively do to encourage someone to leave a radical environment is exactly what you should not do. In other words, very little about this subject is self-evident, and it is high time that a book like this gains wide circulation—especially among those who interact with people who may need help staying away from fundamentalism.

Teachers, in particular, should read this book. Moreover, it is written in a fluid and engaging style, which is rarely seen in fact-heavy literature.