Professional learning can support teachers in developing their understanding of how to position students as agentic and authoritative - a rarity in most classrooms. We analyzed teachers' discourse during professional development focused on agency and authority in middle school mathematics classrooms. We found that teachers frequently engaged with ideas related to student agency and authority. Though less common, episodes in which teachers constructed new ideas and critiqued existing ones indicate that using activity prompts, practicing responsive facilitation, normalizing critical stances, and positioning frameworks as tentative are important for supporting deeper engagement with ideas related to student agency and authority. (c) 2022 Elsevier Ltd. All rights reserved.