For centuries, teacher professional development has largely been done by external experts who advise teachers on how to improve classroom practice and learner performance. This research explores a relatively unchartered idea of history subject panels/clusters as an innovation meant to break away from orthodox teacher professional development spearheaded by external experts. The research adopts a qualitative case study design. One history subject panel was case studied to examine how teachers initiated and sustained improvements in classroom practice and learner performance. Eight history teachers, who were active participants in the panel, were purposively sampled out of 25 teachers who constituted the history subject panel. Data were gathered through semi-structured interviews, document analysis and focus group discussion. Symbolic interactionism was used as the theoretical lens to gain deeper insights into how teachers socialised and shared ideas in the subject panel. Results indicated that the history subject panel was involved in the induction of new history teachers into the profession and the creation of learning communities for history students; practices hitherto undocumented in existing literature on subject panels and teacher networks. Results also showed that the activities of the history subject panel improved teachers’ classroom practice. The implications of this research are that teacher-led subject panels need to be nurtured and supported so that teacher-driven continuous professional development can be enacted across all the subjects offered in the school curriculum. Subject panels can reduce schools’ dependency on external experts for teacher professional development, making teachers the proverbial doctors who can heal themselves.