The purpose of this research was to better understand affordances and constraints of the Candidate Mentor Supervisor Model (CMSM) as experienced by teacher candidates and their mentor supervisors. The results indicated perceived benefits to teacher candidates. Candidates participating in the CMSM reported a sense of nested support within their supervision team during the student teaching experience. Candidates found having a site-based supervisor provided them immediate feedback and support on issues of teaching and learning. Candidates reported the value of a second on-site support person contributed to a developing security as a new professional, reporting support similar to induction phase mentoring from a mentor supervisor. Such support included emotional support, collegial support and teaching support for survival. Additionally, candidates noted the frequent observation by university and school personnel contributed to a sense of ease when engaging in the supervision cycle. Mentor teachers serving in the role of supervisors identified a strength of the model as providing them embedded professional development. The structure of the model made it possible for mentor teachers to engage in peer and near-peer observation. As a result, the mentor supervisors found themselves noticing and reflecting on instructional and management practices which were directly reflected in their own practice. This single case study included university field supervision through a facilitator, a mentor teacher and a site-based practitioner serving as a candidate supervisor. Seven teachers and eight candidates at four different elementary schools participated in the research. Through analysis of interviews, documents, and artifacts, the research sought to uncover the perceived impacts of the model on preservice and practitioner professional development. The results indicate strengths in the CMSM model which could provide opportunities for partnerships in teacher preparation that may serve the professional needs of candidates and practitioners. [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.]