Social justice leadership encompasses all categories of students who have been marginalized or who have been denied equity in education. Social justice leaders provide quality educational experiences for all students, prevent the marginalization of student populations, and improve student achievement across all groups. Many school superintendents are confronting social injustices, and research indicates that their deep commitment to all students in their schools, communities, and an establishment of a more empathetic society can be influenced by their personal and professional beliefs about diversity. My exploratory research focused on assessing superintendents' personal and professional beliefs about diversity and their self-reported actions that are creating conditions for more equitable educational opportunities across diverse student populations. I found a relationship between my participants' personal and professional beliefs about diversity and significant differences in levels of diversity belief by education attainment and school district location. I also found a lack of focus on diversity when the participants were asked to share actions that would address student inequities. My findings have implications for preparing and providing professional development for K-12 school district superintendents. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]