This study examined Communities of Practice (CoPs) composed of senior teacher educators. Our goals were: (1) to identify factors that contribute to or hinder the success of CoPs, (2) to consider the characteristics that help CoP coordinators be effective leaders. The research used qualitative data-collection and analysis. It targeted inter-organizational CoPs supported by the MOFET Institute in Israel, interviewing 23 participants and 12 coordinators of 13 different CoPs.