In this article, I discuss the status of teaching as a profession using Gardner and Shulman's framework emerging from their empirical examination of the professions in America and use Bernstein's sociology of knowledge to help explain how recontextualizing agents struggle to dominate the construction and interpretation of professionalism in teaching. I use data from a major cross-national study of university-based teacher education to illustrate efforts to define the professional knowledge needed for teaching and the wide degree of variability in the opportunities provided to teachers to learn such knowledge. The essential role of teacher education in sustaining the teaching profession emerges very clearly from these analyses. I conclude that the education field needs to develop the capacity to ensure teachers' professional learning and that these efforts need to be informed by use-inspired research and an inquiry culture in university-based teacher education programmes.