The goal of this study was to understand how a secondary principal uses a distributed perspective of leadership to support informal teacher leaders (ITLs) to improve classroom technology integration. Using a phenomenological lens, I employed a multi-site case study to inform the research goals. A conceptual framework based on Bandura’s (1977) social learning theory and Wenger’s (1998) communities of practice theory was used to guide the study’s methods and data collection. Data were collected in three phases. At each site, the first phase consisted of a digital survey with only closed-ended questions that was administered to all classroom teachers. The survey was analyzed using social network analysis to identify the ITLs at each school. During the second phase, individual interviews with the ITLs and the principal as well as a follow-up focus group interview with ITLs at each school were conducted. During the final phase of data collection, I observed the ITLs at work to understand how they embodied informal teacher leadership. Analyses of diverse data revealed how a principal influences the nature of informal teacher leadership in a school. Findings revealed that principals establish cultural expectations using teacher voice in leadership decisions, modeling the effective use of education technology, providing in-school and out-of-school leadership opportunities for ITLs, and establishing expectations for all teachers to assume roles of instructional leadership. It was clear in this study that although principals are not directly connected to the informal leading and learning network that occurs in a school, they indirectly influence the informal network by establishing school-wide cultural expectations for informal teacher leadership and by personally interacting with the ITLs.