Purpose: The purpose of this study was to examine Collins' good-to-great Level Five leadership attributes, as demonstrated by the leadership behaviors of superintendents of high-performing California public single-school districts. Methodology: The researcher used a case study design to conduct this study. Personal interviews were conducted in each of the six identified districts to address the study's research questions. Archival data were also collected to confirm and corroborate interview data and to provide real-life exhibits of superintendent behaviors. Personal interviews were conducted with each superintendent and key district stakeholders, including board members, key staff, teachers, and the principal, where employed. The researcher individually interviewed each superintendent. Some stakeholder interviews were held within focus groups, with up to six interviewees, while others were individual. Stakeholders were advised that no individual would be identified by name, but only by role or responsibility, in the report of findings. Interview questions were based on key concepts from Collins' good-to-great study. Each interview question matched one of the good-to-great Level Five leadership attributes. Collected archival data included mission and vision statements, tenets and belief statements, district memos, strategic plans, district goals, board agendas, and policies. These data were analyzed to confirm, corroborate, and illustrate stakeholder and superintendent interview results. Findings: The researcher collected 226 critical incident examples of superintendent Level Five leadership behaviors in these six cases. Findings represented critical incident examples of each of the five Level Five leadership principles, with multiple examples cited by multiple stakeholders for several of Collins' principles. Conclusions: The results of this research produced a wealth of examples of good-to-great superintendent Level Five leadership behaviors, confirmed by district stakeholder interviews with board members, teachers, key staff, principals, and the superintendents themselves. The research indicated significant adherence to Collins' good-to-great principles, as demonstrated by the superintendents of the six high-performing district cases reviewed. The researcher discovered nearly all critical incidents to adhere closely to Collins' Level Five leadership principles, with several outstanding examples. In only one example was the critical incident described as being only an indirect representation. [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/en-US/products/dissertations/individuals.shtml.