Salafism in Jordan by Joas Wagemakers is one of the best academic books I have read in a while. I recommend it to scholars and students whose research touches upon Islamism, Salafism, jihadism, Jordan and the Middle East. The introductory parts provide a very clear explanation of the finer points of Salafi thinking, and a typology of the Salafi actors within Jordan – its categories being applicable to analyses of the wider movement. The book then turns to a detailed and fascinating examination of how the Jordanian Salafi landscape has evolved over time: the thorny relationship between the different factions and how they have positioned themselves vis-à-vis counterparts regionally and vis-à-vis the state. Through reading the book I also gained insight on Jordanian society, the Kingdom's internal politics, and its role in the region. As pointed out by the author, Jordan is somewhat understudied in research on the Middle East. The thorough, field-work-based investigation that underpins Wagemakers' analyses surely makes this book a major contribution to filling the voids. Finally, Salafism in Jordan is useful as a guide to reading primary sources in Arabic by Islamists and jihadists. Because the author makes extensive use of Salafi writings and interview data, readers get the chance to familiarize themselves with their terminology. All ideological expressions and concepts that are explained are also accompanied by accurate transliterations. I usually find that a bit annoying, but here it makes sense, and is a value added to an otherwise excellent study.