This paper introduces "lesson study" as used in Japan to improve instruction. Lesson study is the process of planning, conducting, and discussing the research lesson for teachers to study. Four features are identified as essential to Japanese lesson study: (1) a shared long-term goal for teachers; (2) important lesson content; (3) careful study of students; and (4) live observations of lessons. Teachers learn from lesson study and research lessons because of the opportunity to think carefully about goals of the particular content area , unit, and lesson and about long-term goals for students. Research lessons give teachers a change to learn from other teachers, and they offer a way to deepen knowledge of subject matter. Studying research lessons helps a teacher develop instructional expertise and build the capacity for collegial learning. They allow the teacher to develop "the eyes to see students." Several features of the Japanese educational landscape support lesson study, including a shared and frugal curriculum, established collaboration, a belief in improving teaching through collective effort, and the practice of critical self-reflection. Japanese teachers face a certain stability in educational policy and tend to focus their instructional improvement time on instruction as they maintain a focus on the whole child. Some of the barriers facing lesson study in the United States are described. (Contains 48 references and 12 endnotes.) (SLD)