There is a defined need to provide accessible and effective professional development for 4-H educators. Lesson study is a Community of Practice-based approach to educator professional development. Prior research has shown lesson study to be effective with 4-H staff, adult volunteers, and teen volunteers. This inquiry, a multisite case study, was designed to investigate the application of lesson study in authentic contexts with 4-H county agents from 1890 land-grant universities. Quantitative and qualitative measures revealed improved preparedness, participation, and camaraderie among participating educators. Other benefits to participants included improved lesson planning and implementation.