As expectations for improvements in public K-12 education continue, principals and teachers need to collaborate for continuous school improvement. Innovative change is needed to meet the needs of students. Michael Fullan's change theory (1993) identified many inhibitors to change, such as the human tendency to avoid change due to vulnerability and fear, high stakes accountability, parent pressure and, in contrast, maintenance of the status quo. In Wisconsin, the passage of Act 10 posed new threats to innovation. Both Robert Marzano (2004) and Kathleen Cotton (2003) explored principal practices and behaviors associated with student learning, but it is important to extend that research to understand the impact of principal behavior in high performing schools. The purpose of this study was to explore the impact of middle school principal practices and behaviors on innovative instructional practices of middle school teachers working in high performing, high pressure school environments where risk-taking and innovation can sometimes be challenged and inhibited by the pressures associated with failure and vulnerability. Seven high performing middle schools were identified using data where students scored 90% proficient or above on state standardized tests in reading and math. The staffs of all seven schools took a reliable survey measuring school culture and three were selected for study. Each staff identified faculty for interviews in addition to the principal. Finally, a confirmatory focus group was held in order to reinforce and deepen understanding of the findings. Six key principal leadership behaviors and practices were identified. Five main themes including relational practices, shared leadership, support of risk-taking, role modeling and observation, feedback and evaluation emerged from the interviews. During the confirmatory focus group, two additional themes emerged as "assumed high expectations," and "balancing focus on student learning and staff emotional support." One of the seven themes, teacher observation, feedback and evaluation, was not deemed as supportive or effective in supporting innovation given the perspective of teachers. [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.]