Teacher educators piloted the use of the Reformed Teaching Observation Protocol (RTOP), a peer observation instrument associated with increases in learning in science and mathematics teacher education courses. Faculty participants received a series of trainings in RTOP use and rated each other's teaching during multiple peer observations. The purpose of this study was to investigate whether the RTOP would prove useful for formative and summative purposes across teacher education courses in general. While participants saw value in the peer observation process and the RTOP instrument, findings suggest that the perceived formative functions of the RTOP outweighed the instrument's summative value.