This document outlines the process of lesson study, a form of teacher professional development used in Japan. It involves groups of teachers collaboratively planning, observing, and refining lessons to address an identified area for development. The steps include: choosing a focus area and research question; planning the initial lesson; delivering and observing the lesson while collecting data; reviewing and identifying areas for further development; planning and delivering subsequent lessons to continue iterating on the research question. Benefits include encouraging teacher collaboration, reflection, and using an evidence-based approach to evaluate teaching methods. The process aims to help teachers take ownership of their own professional learning and continuously improve instruction to better meet student needs.