In recent years, the European perspective in the academic field of Religious Education (RE) has gained increasing importance. This development includes a growing focus on an European perspective regarding the training of RE teachers. This book presents a comparative study of this specific training in 52 European countries, drawing on the comprehensive data set of the “Rel-Edu”-Project. Using a qualitative research design that combines two methods – global evaluation and Grounded Theory – the study generates comparative findings that, for the first time, map the training of RE teachers across such a large international area. Through systematic organization along eight identified categories derived from a remarkably unique European data set, similarities and differences in RE teacher training are identified. At the same time, the study offers a critical reflection on the methodological potential and limitations of large-scale comparative research. The book contributes to greater conceptual clarity in European RE and provides a foundation for further international qualitative empirical research in this field.