In 2011, protesters in Tunisia and Egypt overthrew their autocratic leaders and demanded sweeping economic and political reforms. Yet since then, the two countries have seen very different outcomes. Tunisia has built a shaky democracy; Egypt has sunk back into authoritarianism. Several of the essays in this collection set out to understand why. One contributor, Rached Ghannouchi, the leader of Tunisia’s Islamist party, Ennahda, explains its history of cooperating with other parties. After the revolution, Ennahda advocated a system of proportional representation, preventing itself from winning national elections outright and provoking a backlash from “the deep state,” precisely the mistake that Egypt’s reformers later made. Ghannouchi’s successful pragmatism stands in contrast to the clumsiness of Egyptian President Mohamed Morsi, who was deposed in 2013, just a year after taking office, following widespread protests. Tunisia was also helped by its tradition of civilian control of the military, whereas in Egypt, things were the other way around. Finally, Tunisia took an extended period to write its constitution; Egypt did a rushed job. Despite its subtitle, the collection does not consider every part of the Muslim world (although it does get beyond the Middle East, with fine chapters on democracy in India and Indonesia). Nevertheless, it is an important and often original work.