This article explores the nature of reflective practice in a professional development process based on lesson study. The authors examine how a lesson study model initiates reflection as a meta-action scaffolding reflective practice among teachers of English as a foreign language (EFL) at a university in Turkey. Fieldnotes, interviews, and audio diaries were used to collect both introspective and retrospective data. These data sources enabled the researchers to focus on reflective action both as a process and as a product. Using thematic content analysis, the research demonstrates how reflective practice permeates lesson study as teachers reflect on their practice both individually and collaboratively. Moreover, the research also shows how teacher agency can be promoted in reflective practice throughout lesson study. The findings reveal how reflection as meta-action in lesson study can support transformative teacher agency among EFL teachers.