Linking theory and research on positive psychology and positive organisational scholarship, with a focus on positive leadership, this article provides a conceptualisation of teacher leadership as an intentional reflective process of learning to grow wellbeing for self and others. Aligned with increasing international research on the importance of wellbeing in schools, the author suggests teacher leadership may have a role to play in cultivating school cultures that foster wellbeing for all. In this way, teacher leadership is assumed to be a mindset, a way of seeing the work of leadership as an opportunity to build collective capacity for growing wellbeing as central to school improvement work. Further research is needed to determine the benefits and potentials of developing and supporting positive teacher leadership in schools.