This study investigated principal leadership in building a culture of disciplinary literacy. Previous studies investigated and validated the uniqueness of disciplinary literacy (Moje, 2015; Shanahan and Shanahan, 2008; Spires et al., 2018). Case studies on individual schools looked at literacy within the context of a specific school community (Faulkner, 2012; Francois, 2014; Gilrane et al., 2008). These studies, although they touched on teacher and principal leadership, did not focus on leadership at the core of creating a community of literacy. This study focused on the essential actions and dispositions of principals who successfully built and maintained a culture of disciplinary literacy. Eight principals from a large, suburban Northeastern school district were interviewed to ascertain their actions. Open coding with constant comparative analysis yielded common themes, dispositions, and actions of principals. Common leadership themes emerged as principals discussed leading disciplinary literacy: demonstrate why change is needed, recognize that leading literacy requires a plan, link the district priorities to disciplinary literacy, distribute leadership, provide targeted professional development, and utilize established resources. What emerged from this study was that one person alone could not build a culture of literacy within a school. Rather, changing instructional practices to put literacy at the center of learning requires the community to embrace literacy. As school leaders look to improve equitable outcomes for all students, they must look at the variation in instructional practices across the disciplines and ensure that literacy research-based practices are being used across all content areas. Change of this magnitude is a multiyear shift with student learning at the center of all instructional decisions. The complex task of leading instructional change requires a principal to learn about disciplinary literacy. If schools want equitable education for all students, principals must understand and place priority on disciplinary literacy. / 5 / This study investigated principal leadership in building a culture of disciplinary literacy. Disciplinary literacy is the ability to read, write, think, and discuss like an expert in the field. For example, classes with disciplinary literacy at the core would ask students to read like a scientist or write an original score like a musician. Previous studies investigated and validated the uniqueness of disciplinary literacy (Moje, 2015; Shanahan and Shanahan, 2008; Spires et al., 2018). Case studies on individual schools looked at literacy within the context of a specific school community (Faulkner, 2012; Francois, 2014; Gilrane et al., 2008). These studies did not focus on principal leadership at the core of creating culture of disciplinary literacy. This study focused on the essential actions and dispositions of eight principals who built a culture of disciplinary literacy in each of their secondary schools. Common leadership themes emerged as principals discussed leading disciplinary literacy: demonstrate why change is needed, recognize that leading literacy requires a plan, link the district priorities to disciplinary literacy, distribute leadership, provide targeted professional development, and utilize established resources. As school leaders look to improve equitable outcomes for all students, they must look how literacy is taught in the disciplines and ensure that students have an opportunity to learn the real-life practices of professionals in the field. The complex task of leading instructional change requires a principal to learn about disciplinary literacy, so he or she can encourage teacher-experts to explicitly teach authentic disciplinary literacy skills in their classes.