With the passing of Act 82, the state of Pennsylvania has provided school districts with Danielson's Framework as a tool for principals to evaluate teachers. The purpose of this study was to determine the perceived professional development needs of Pennsylvania principals as they implemented the new educator effectiveness system. Three hundred principals from across the state participated in the study. The findings of this study suggest that principals who participated in this study were confident in assessing the elements in Domains 2 and 3 of the Framework. Principals have the most confidence in evaluating Component 2d: Managing Student Behavior and 2a: Creating an Environment of Respect and Rapport. The component principals have the least confidence evaluating is 3d: Using Assessment in Instruction. When the elements were examined in unconventional, but logical groupings, it was found that assessment in instruction continued to be the grouping that principals had less confidence in evaluating. Elements associated with student ownership of the learning were the elements that principals had the least confidence in evaluating. This study extended the literature on teacher evaluation by recognizing that principals are confident in evaluating teachers using the Framework. Evaluating teachers based on the actions of their students as indicated through classroom observations may be an area to examine in more depth. This study also extended the literature base by identifying the preferred professional development formats in which principals would be most willing to participate. It was found that district and I.U. sponsored workshops were the preferred format for professional development. University course work, whether on campus, online, or a hybrid of the two, was the least favorable means of professional development for principals. The findings suggest that those providing professional development for principals would do well to examine how principals are able to collect evidence to support the students' learning and participation in the learning process. Also, professional developers, including school districts, intermediate units, and universities, should offer professional development that is relevant to the demographic population through workshops, mentoring/coaching sessions, or small study groups. [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.]