This study examines factors impacting teacher learning during and after an online professional development program focused on teaching English language learners in U.S. schools. Research focused on nonbilingual K-12 teachers' changing perspectives on the role of students' native languages in classroom teaching and learning during and after the professional development program. Case studies of two teachers suggest that teachers who do not consider themselves bilingual do not necessarily hold negative views about native languages but that they require institutional support to move beyond "honoring" native languages to incorporating them into daily instruction. Further, institutional support for native-language use can be influential in changing teachers' practices and perspectives.