For the past 20 years, countless reports have been issued calling for reform of undergraduate education to improve student learning, persistence, and graduation rates for students in science, technology, engineering, and mathematics (STEM) majors. However, by many measures, recommendations in these reports have not been widely implemented. While it is known what changes are needed, systemic change in higher education has proven difficult. Institutional, regional, and national communities that are focused on providing knowledge, support, and exemplary models for STEM education have been identified in reports as important vehicles for creating changes, yet there is little systematic research on these communities. STEM communities of practice that exist at the national and regional level involve thousands of faculty. This article will examine the overall study of the formation and sustaining of these communities of practice, benefits of involvement, and design of communities to support faculty. Also, examined will be how these communities can be best designed to engage faculty in STEM reform work.