This article reports on a joint action research study about principals’ pedagogical leadership and what happens when principals explore pedagogical leading. In this study, the theory of practice architectures interacts with the method chosen for analysing the processes and results. Partnerships between universities and practitioners are seen as an important arena for professional development, and the results of this study illustrate how cooperation between scholars and practitioners can promote professional learning and capacity building amongst both parties. The findings show how trustworthy relationships are necessary in order to change the practice and evolve a critical and emancipatory approach among the participants. Student learning and development appear to be important components of the principals’ pedagogical leading. Pedagogical leading is about arranging the conditions for teachers so that they are given the opportunity to improve their teaching. Pedagogical leaders do not only talk about changes but also call for concrete actions in schools’ internal work. Principals’ pedagogical leading involves orchestrating the surrounding arrangements in such a way that they enable school’s learning and collaborative practices. Part of this orchestration involves supporting forms of cooperation so that good norms and a culture that nurtures development are established.