The shift towards school-led teacher education steered by the government in England challenges the "traditional" model of experienced teachers leaving school and entering the higher education sector to become teacher educators. More teachers are undertaking the dual role of teacher and teacher educator, leading the professional learning of teachers. This paper investigates the perceptions of seven experienced teachers who take on the role of leading the development of subject knowledge of new and experienced teachers through a case-study approach. The findings reveal that leading professional development has an impact on the professional identity of these teachers. This new role has changed the way that they view themselves as teachers, and their practice as teachers, and for others it has contributed to their leadership role and career progression. Not all of the participants embraced an identity as a teacher educator. The findings are compared with teachers making the transition from school teacher to teacher educator in higher education institutions in the literature, to discover commonalities that could guide the planning of professional development opportunities. The research revealed insights into experiences of becoming a teacher educator; the impact on them as teachers and leaders; and how they see their own identities developing.