Blending principal education programmes and leadership practice has become a common feature in the education of school principals. However, the need for further research in how programme participants experience learning within an overall structure of a programme has been highlighted since the same programmes are experienced differently. This empirical study used a practice-based approach to explore how participation in the Swedish National Principal Training Programme intertwines with principals' work in practice. A situated perspective was used, interviewing and observing principals in both their educational and their workplace practice. In addition, teachers were interviewed at their school. This study revealed processes of continuous learning, which connects practice to what was learned in the Principal Programme. These processes mend and bridge old practices with new practices and therefore facilitate change. The principal also becomes a broker, rendering legitimacy in practice. The analyses, however, also reveal processes of interrupted learning, which disconnects working in practice from the participation in the Principals' Programme, leading to discontinuous processes and exits. Increasing consciousness of the value of working with bridging and brokering would support principals' professional learning and function as a foundation for leadership development.