Sharing experiences among teachers is an important part of professional development. Coaching is defined as an ongoing process in which experts engage with practice, with the purpose of continuous improvement. This article will discuss the principles of peer coaching in teacher development, by examining a specific case of peer coaching between two experienced teacher educators. From this analysis, we derive two major concepts as guiding the process of peer coaching: "joint deliberation" and "metapedagogy." These two features are conceptualized using excerpts from the case study and from the literature.