Evaluating the quality of teaching in higher education institutions frequently relies on student ratings, which are popular and efficient, but biased and ineffective. Peer review of teaching warrants investigation for its usefulness in the tenure and promotion process within higher education institutions. A peer review of teaching study also has potential benefits for other instructors who seek to improve their teaching. This mixed methods study evaluates a proposed approach to peer review that is being considered for adoption across all colleges at Brigham Young University. This proposed approach includes peer observations and a submission of a professional teaching portfolio designed to follow the current research of best teaching practices and sustain ethical and professional standards. Data were gathered from 107 participants in treatment and control groups in the form of pre- and post-surveys and focus group interviews. A 2x2 Split Plot ANOVA was used to analyze continuous variables to determine interaction and main effects between groups (pre/post x experimental/control groups). We used a constant comparative method to identify themes in focus group responses, using open, axial, and selective coding of participants' focus group interviews (Glaser & Strauss, 1967). Global themes identified were the positive and negative impacts of the peer review of teaching process. Most of the positive impact themes were gathered from those who had participated as peer reviewers, whereas much of the negative impact themes were gathered from those who had experienced a peer review of their teaching. Significant interaction effects between the assignment of treatment and time provide corroborating evidence for the themes identified. The results from this study provide better understanding of the peer review of teaching process that can ultimately lead to better evaluation practices as well as improved teaching and learning for higher education institutions.