This paper draws on data collected as part of the larger study of professional learning (PL) in Canada. The article specifically explores the work of teachers' organizations (also known as teacher unions) in leading and supporting high-quality learning experiences for their members. Adopting a progressive view of teacher organizations, the paper positions such organizations as an integral component in teacher PL. The findings highlight the ongoing professional agendas of teachers' organizations with the aim of deepening the space for further collaborations between teacher organizations and other educational stakeholders in the area of PL.