This paper introduces and summarises a programme of German research into teaching started 20 years ago. This research draws on Herbart's analysis of teaching with its focus on 'Bildung' (formation) which is distinguished from the measurement/psychometric tradition. It offers the possibilities of a deeper empirical understanding of pedagogical practice in terms of (i) education, (ii) formation, and (iii) didactics. The paper sets out four pedagogical assumptions drawing on empirical experience. It proceeds to a discussion of methodological principles to show what it means to reconstruct teaching using a hermeneutic approach involving a sequence analysis of lesson transcripts. The approach is also recommended for teacher professional learning through offering alternative ways of problem solving.