Mouline takes readers inside the Wahhabi religious establishment of the kingdom of Saudi Arabia. Wahhabi clerics, known as the ulama, have been allied and have occasionally intermarried with the tribal House of Saud since the 1740s. In the twentieth century, the clergy went from shunning interaction with many other Muslims, let alone non-Muslims, to engaging with the wider Muslim world—and to some extent with the non-Muslim world as well. On most issues, the political leaders of the kingdom have proved more open than the clergy to change—for example, by introducing the concept of “positive,” human-made law to the legal system. Still, the clergy has always elected to adapt rather than to confront the monarchy, for fear of producing fitna, or dissidence. At the same time, the clergy has never been marginalized, and through the Grand Council of Ulama, it plays a critical role in decision-making on education, the judiciary, public morality, and business and finance. Mouline makes no predictions about the sustainability of this arrangement, but his account makes clear that, even after a few centuries, it remains viable.