Action research (AR) is a form of systematic inquiry by which practitioners address their own problems of practice. Professional development (PD) is a means by which teachers contribute to school improvement and student achievement. Too little research has gathered the qualitative perceptions of former participants in action-oriented professional learning programs, particularly in the realm of single-sex independent schools. This study's goal, therefore, was to gain insight into how teachers recall experiencing action research as professional development. Two evaluation questions guided the study: (1) To what degree does the Saints Action Research Program reflect an effective model of professional development as evidenced by each of the five levels of Guskey's model for evaluating professional development? (2) What are the perceptions of program alumni and the instructional leadership team regarding the advantages and limitations of participating in the Saints Action Research Program? To answer both questions, I generated data from four sources: (a) a participant survey, (b) semi-structured participant interviews, (c) a document review process of participant research briefs, and (d) a group interview with the instructional leadership team. Collectively, their experiences revealed that they practice action research as a multi-step process. However, the process is not ongoing, nor does it account for student learning outcomes. Instead, action research is time-consuming because the program requirements do not sufficiently differentiate based on participant needs. Ultimately, these findings offer strong support for discontinuing the current iteration of the evaluand; fill a qualitative gap in action-oriented teacher-led projects; and offer facilitators of professional development insight into how these teachers understand and practice action research as professional development. [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.]