The purpose of this grounded theory study was to identify the need for educators' use of lesson study as a professional learning community to increase communication between colleagues. Lesson study is considered a form of professional development in that, educator colleagues work with one another to plan, implement, critique, and revise a lesson in order to improve instruction, teacher learning, and student achievement. Accordingly, this study includes a review of the various theories related to lesson study and professional development: behavioral, grouping/tracking, contingency/situational, constructivist, and adult learning. The research questions in this study examined the need for educators to uncover the effect of the lesson study process on language arts curriculum, teacher learning, on student achievement, and on the description of each participant's experiences with lesson study. The sample of the study included 6 third grade teachers, 2 resource teachers, the principal, the vice principal, and 20 students at a rural elementary school in a western U.S. state. Notes from interviews, observations of lesson study, a focus group, and artifacts from portfolios were coded and categorized identifying themes and patterns using a two-step grid. Results from this study indicated that lesson study gave the educators the opportunity to collaborate together in a structured amount of time, provided a focus for teaching, and ensured a reflective teaching practice. Additionally, these findings open the possibility of a social change because the school adapted the way of conducting everyday business. Lesson study gave the participants the opportunity for teamwork, to become reflective professionals, and to improve schooling for all stakeholders in the school. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]