Despite the magnitude of the investment in professional development (PD) for K-12 educators and its limited returns, research on PD has typically only focused on effective elements of program design. Little work has been done to explore the role of facilitators or leaders of professional development. However, by better understanding the complex role of PD leaders, we can better understand how they impact the outcomes of PD programs. This qualitative study closely examined the role of four PD leaders in order to learn what they believe to be the critical aspects of their role and how their beliefs about PD guided their planning and facilitation of the PD experience. Using a multi-case study approach, these PD facilitators were interviewed and videoed facilitating a PD session. Following this, participants viewed their video with the researcher to unpack aspects of their facilitation. Particular focus was given to facilitators' beliefs about PD, how those beliefs informed the development of PD, and what PD practices were or were not used in the enactment of PD. The results of the study include a list of 16 aspects of leading PD that help to decompose the role. Additional insights include how the naming of aspects and the video observation processes were beneficial to the participants as professionals. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]