Book excerpt: Renewing Islam by Service offers a theological account of the contemporary Turkish faith-based service movement started by Fethullah Gülen, and placed against the backdrop of changes in modern Turkish society. The life and works of Gülen are analyzed against the background of developments in Turkish society, and of spiritual Islamic tendencies in the transition from the Ottoman empire to the secular republic. Pim Valkenberg includes stories of his personal experiences with supporters of this movement, in a number of dierent countries, and analyzes the spiritual practices and the faith-based service of this movement that is also compared to some important Christian religious movements.