That teaching constitutes the “core business” of teachers (Giesecke 1985) is an unquestioned tenet of school, teaching, and professional research. However, it remains empirically unclear to what extent this assumption is shaped by teachers’ professional development. This article therefore adopts a (professional) biographical perspective and asks to what extent teaching represents the “core business” for teachers in later phases of their careers. The study is based on a reconstructive longitudinal study that examines the (professional) biographies of fifteen teachers over their first ten years in the profession. The results show that the perceived significance of teaching as the “core business” shifts in a variety of ways in later years of teaching, thus allowing the concept to be empirically questioned.
