This correlational study examined the relationship between leadership behaviors exhibited by superintendents and the collective efficacy of their leadership cabinet. Irby, Brown, and Duffy's Synergistic Leadership Theory provided the framework for the study with explicit focus on the Leadership Behaviors component of the tetrahedral model. Exploration of the links between the leadership behaviors included in the Organizational Leadership Effectiveness Inventory (OLEI), developed by the authors of the theory, along with leadership behaviors associated with Bingham's Traits Theory, Burn's Transformational Leadership Theory, and Greenleaf's Servant Leadership Theory provided a foundation for this study. Superintendents from unit school districts in Illinois provided demographic and organizational information and leadership cabinet members from those districts completed a survey comprised of items from the OLEI and the Collective Efficacy Beliefs and Collective Outcomes Expectancy components of the Riggs, et al Self-Efficacy and Outcome Expectancy Scales. Using Pearson Bivariate Correlation analyses, the study identified six leadership behaviors with large correlations and high significance to collective efficacy. Each of these behaviors aligned with transformational leadership attributes. Four leadership behaviors associated with servant leadership were identified with medium correlation and high significance to aspects of the organizational structure of leadership cabinets. The findings from this study have implications on the leadership choices of superintendents, Board of Education hiring, feedback and community engagement practices, state policy as it relates to training and development of superintendents, and universities as they develop and provide coursework and experiences for superintendent endorsement programming. [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.]