The principal plays a key role in establishing a culture of collaboration and ongoing learning, and his/her actions related to effecting change are vital to the success of the school. A principal can contribute to the advancement of teacher expertise by engaging in specific behaviors. One such behavior is focused feedback, which leads teachers to reflect on their instructional routines. Given with intentionality, it is a powerful tool. Therein lies the motivation for this study. The purpose of this qualitative, phenomenological study was to examine the practices in which principals engage during classroom post-observation feedback, and their effect on teacher professional growth. Seven teachers at 2 Southern California Catholic high schools were interviewed to capture their perceptions of the effect that principal feedback has had on their professional growth. Although much research has revolved around the impact that principals' actions have on the enhancement of teacher practice, very little research has focused on these effects from the perspective of the teacher. Capturing teachers' perceptions about the way their principals' actions impact their instructional practice may add to the existing body of knowledge in the field of education related to the way principals promote the use of effective practices at their schools. It may also shed light on the need for the teacher's voice to be heard and taken into consideration when making decisions on and implementing policies that are directly related to improving teacher practice. Three main ideas emerged from a review of the existing literature: (a) "there is a direct connection between the principal's actions and teachers' professional growth"; (b) "principal feedback produces lasting changes in instructional practice, especially when given immediately following the teaching"; and (c) "teachers are reflective practitioners seeking to improve their practice on an ongoing basis." Educational institutions may be able to utilize the findings of this study to inform their practice, and or to re-examine their policy on evaluation processes. [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.]