Religion and secularism have been central threads in Turkish politics throughout the history of the republic. This chapter focuses on three important aspects of the relationship between religion and politics in contemporary Turkey. First, it explores the political functions of the Directorate of Religious Affairs (Diyanet), a government agency that has served as the primary means for the implementation of the religious policies of the Turkish state. Second, it investigates the relations between Islamic communities, political parties, and the state and argues that the distinction between official and unofficial Islam that has informed much of the work on the Turkish religious field must be strongly qualified. Finally, the author focuses on the trajectory of political Islam in Turkey, critically reviewing the literature on the rise, political incorporation, and authoritarian turn of Islamic parties. The conclusion emphasizes the need for studies investigating the impact of politics on religiosity in Turkish society.