Fethullah Gülen is Turkey’s most famous, influential, and controversial faith-based communitarian leader. Collectively known as “the Gülen movement” (GM), individuals inspired by Gülen’s charismatic teachings control organizations that span the world. Led by “aksiyon insanları” (people of action), the GM has accumulated tremendous social influence in education, media, trade, and allegedly, in unelected state office. Responding to those critical of its power, GM actors claim to be nothing more than “selfless,” “service oriented” advocates for interfaith and intercultural dialogue. The effort of this introduction to this special issue of Sociology of Islam is to situate the GM in its Turkish context. As a collective actor, the GM creates subjects and impacts societies. The social norms and communitarian social structure that are reproduced in the GM network engender identities, regulate desires, and determine social, economic, and political outcomes in Turkey and around the world. In this way, the GM constitutes a source of social power, and thus warrants academic scrutiny. In an attempt to fill a void in the literature on the impact of the GM’s collective mobilization, the contributing authors to this special issue of Sociology of Islam hope to contribute to the sociological investigation of Turkey’s GM in particular, and to the interactions between Islam and modern socio-political organization in general.