The purpose of this study was to provide a broadly based description of the National Board Certification process and the perceived impact of the certification portfolio on the reflectivity of the National Board Certified teacher and its corresponding effect since completion. "The National Board Certification assessment process focuses on reflection and inquiry. Applicants submit an extensive portfolio that includes videotape, artifacts, reflective commentary, and documentation" (Kantner et al., 2000, p. 227). National Board Certified teachers have all engaged n a sustained structured process of reflection, both reflection-in-action, and reflection-on-action. They form a unique population of teachers who have been involved in the same detailed examination of their practice. Insights about the reflective experiences of these teachers are of great value to the profession. The framework for the production of portfolios supports the reflective act (National Board for Professional Teaching Standards, 1998b). Portfolios provide vessels for recording and document practice. I asked National Board Certified art teachers to consider their reflectivity prior to certification, to examine their own portfolio processes to consider which entries had the greatest impact on their ability to be reflective teachers, and to suggest how the process changed or enhanced their ability to be reflective practitioners. The respondents were invited to comment on any or all of the questions. The sample consisted of 99 National Board Certified art teachers who had achieved certification in Early Adolescence to Young Adulthood Art between 1996 and 2001. Seventy (N = 70) teachers returned the survey which creates an overall return-rate was 71%. There was one primary research question for the study: In what ways has the act of reflection, through the creation of the National Board Certification portfolio, effected, changed, or enhanced the practice of National Board Certified art teachers? A set of sub-questions served this main question: (1) To what extent did National Board Certified art teachers reflect on their practice before undergoing the certification process? (2) How does the development of the NBCT portfolio facilitate reflection? (3) Which parts of the portfolio process had the greatest subsequent impact on enhancing the teachers' practice? (4) To what extent does the teacher now perceive him or herself to be reflective? (5) What aspects of the teachers' practice have been changed or enhanced as a result of successfully completing the process of National Board Certification? The results of this study highlight the personal journey of certification candidates, and they affirmed that a structured, critical portfolio can be a powerful agent for both the encouragement of positive growth in a professional teaching career, and recognition of a cadre of exemplary professionals for mentoring and leadership roles in the school and professional community. This study also demonstrated that reflective thinking is both the catalyst and the consequence of the certification process. (Abstract shortened by UMI.).