The World Association of Lesson Studies (WALS) aims to promote and advance the research and practices focused on Lesson Studies in order to improve the quality of teaching and learning. It provides a platform for research collaboration, mutual assistance and information exchange among its members. It is made up of educational researchers and teaching professionals committed to the improvement of the quality of learning. Lesson Study as a tool for professional learning is now practised in many countries and it has helped schools around the world develop into learning communities. Our annual conferences bring together researchers, school leaders and teachers from various countries to share their experience and practice of lesson studies. They also provide opportunities for participants to discuss current and enduring issues pertaining to teaching, learning and research on Lesson Study.