This contribution will outline the development of a specific approach of theoretical educational thinking in Germany, associated with the notions of "Didaktik"/didactics and "Fachdidaktik"/subject-matter didactics as well as its comparative, generalized form called "General Subject Didactics" (GSD). The first one deals with the 'art and science of teaching' in general, whereas the second and third one relate to disciplines of subject-matter teaching and learning in school. We will start with analysing "didactics" being in a crisis, leading to the strengthening of "subject didactics" in its place. Yet subject didactics has its own limitations and weaknesses. We will argue that these can be overcome with the help of "General Subject Didactics" which observes, compares and analyses the different subject didactics from a higher point of view: this approach can help understand the educational practice of one specific subject better and deeper, but also help moving beyond particular experiences and boundaries within that framework, towards looking at neighbouring subjects, at cross-curricular networking and cooperation. We will demonstrate how this might support the development of a powerful educational knowledge base for specialized subject teachers and their practice as educators as well as for continued professional development.