It is widely accepted that professional learning is a crucial aspect of the ongoing professional practice of educators. But how should this professional learning take place, and what arrangements enable and constrain practices associated with educator learning? In this article, we explore two case studies of action research projects: one undertaken with Australian Vocational Education and Training (VET) teachers, and the other undertaken with Swedish principals. Using the theory of practice architectures and the Professional Learning Framework (see text), we consider what action research team members identified that they learnt through the action research projects, and what enabled and constrained that learning. The findings highlight five key themes that enabled and constrained educator professional learning and supported educators in making positive changes in their professional practice: power and solidarity, trust, recognition, agency and time. Further, reflection and collaboration were also highlighted as important factors in supporting educator professional learning. We conclude that action research can enable educator professional learning, can support the contextualised understanding of what works, how it works and for whom it works, and can enable educators to make positive changes in their professional practices.