This mixed methods study explores how principals are managing and leading their school sites in ways that retain effective teachers, in the context of the value-added approach to teacher evaluation. There is a great deal of research that identifies reasons for teachers leaving the profession. However, there is little research that reviews strategies administrators are utilizing to resolve the problem, especially in the context of the nascent value-added approach. This study looks at the unique situation that is created by the somewhat controversial adoption of the value-added approach to teacher evaluation. School sites were identified through an analysis of retention data and overall test score data to select sites that represent high performance with high and low retention rates and low performance with high and low retention rates. Some of the themes that emerged through semi-structured interviews conducted with principals and teachers were: the importance of a supportive principal in addressing issues relating to retention, the unintended consequences associated with implementation and the impact on school climate. The interview responses provided evidence supporting a finding of the importance of the role of the principal in supporting teachers in the climate of the value-added (VA) evaluations and the overall importance of administrator leadership in retaining teachers in the context of this approach to evaluation. Additionally, the principals' role in mitigating negative aspects of VA on the overall school climate emerged. These findings have implications for school districts in terms of training for principals and for policymakers in the development and implementation of policies that support the retention efforts. [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.]