The lecture deals with the topic of “secularization” from a sociological perspective. First, some aspects of the concept of secularization will be discussed briefly. Secondly, the the distinction between religious and secular will be addressed. Thirdly, it is proposed to apply the distinction between micro, meso and macro processes to the religious sphere. This shows that the relationship between the religious and the secular takes place differently at the micro level of individual actions than at the meso level of social movements, networks and organizations and at the macro level of the relationship between religion and other societal spheres. Against the background of the distinction between micro, meso and macro processes and structures, different figurations of the meaning of religion and the religious-secular distinction can be illuminated. Finally, some aspects of the current religious situation in Europe are examined before some conclusions are drawn.