Purpose: The purpose of this paper is to discuss the developmental stages of lesson study for learning community (LSLC) and to clarify the measures necessary for promoting the progress of LSLC, targeting consultants working on educational development projects for developing countries. Design/methodology/approach: The paper is organised as a conceptual paper. First, LSLC is positioned in the context of literature on school reform, then an explanation of the LSLC framework and the LSLC developmental stages is offered. Findings: LSLC is a systemic school reform activity based on lesson study. However, unlike lesson study models in international literature, the entire school is involved from the very beginning and observation and joint reflection are focused upon across subject boundaries. There are five stages in LSLC development, from confusion at the initial stage to sustainment. Practical implications: Using LSLC, teachers learn how to respond to children and how to enhance the quality of students' learning through mutual observation and reflection. Because of the tendency for teachers to focus on teaching methods and techniques, consultants first have to allow teachers to pay more attention to children. As they become able to describe children and their learning in lessons, it becomes important to let them discuss enhancing the quality of learning. Originality/value: LSLC is a very new approach to school reform and lesson study. Thus, despite the existing literature on LSLC cases in developing countries, few theoretical explanations have been undertaken. This paper targets professional consultants in developing countries and aims to provide a detailed explanation from a conceptual perspective. (Contains 1 table.)