This paper examines turn-by-turn interactions [Wagner, D., & Herbel-Eisenmann, B. (2014). Mathematics teachers' representations of authority. "Journal of Mathematics Teacher Education," 17(3), 201-225. doi:10.1007/s10857-013-9252-5] in mathematics professional development, looking specifically at facilitators' positioning of supporting English language learners (ELLs), using ethnographic microanalysis [Erickson, F. (1992). Ethnographic microanalysis of interaction. In M. D. LeCompte, W. L. Millroy, & J. Preissle (Eds.), "The handbook of qualitative research in education" (pp. 201-226). San Diego: Academic Press, Inc.]. This study took place in a weeklong professional development for seven teacher leaders preparing to facilitate mathematics professional development at their schools. Two facilitators led the professional development. The findings demonstrate how facilitators positioned supporting ELLs as "important for all" and "important for some" and how their participating teacher leaders responded to this positioning, either accepting or rejecting it. This research highlights the link between positioning authority, which attends to the relationships between comfort, knowledge, and authority, as well as how individuals might develop such authority. This paper begins a conversation about the role of positioning in professional development, specifically linked to facilitators' positioning and the importance of authority in creating professional learning experiences focused on supporting ELLs.