Objective/Research Question: This paper reports on data collected in a multi-year National Science Foundation grant project involving a professional development (PD) model built to support community college faculty as change agents (CAs). The research question was: How do disciplinary communities of practice (CoP) emerge among community college faculty working in teams? Methods: This research employed a mixed-method design. Data collection included interviews, focus-group sessions, reflective journals, observations, end-of-workshop evaluations, survey data with the 23 geoscience faculty CA, and data from a national survey. Data analysis used the principles of CoP. Results: When compared to other community college geoscience faculty nationally, the participants in our study reported greater levels of behaviors characteristic of CoP. The CoP emerged due to network building and resource sharing within the PD. The findings highlight the significance of structured PD on the development of robust disciplinary CoP. The initial orientation of CAs, existing institutional structures, and cultures of community colleges influenced the CoP. Putting lessons learned into practice, sharing outcomes, and leading regional PD for others contributed to strengthening of the CoP. Conclusions/Contributions: Intentional PD catalyzed the emergence of strong CoP among the community college geoscience faculty participants. The opportunities to connect with disciplinary colleagues teaching in community colleges who shared an interest in supporting student success and improving teaching practices and the opportunity to share lessons learned contributed to the CoP. Structured interactions, critical reflection, and leading colleagues in PD supported developing, maintaining, and growing the CoP.