The purpose of this scoping review is to explore what the literature says about the use of peer observation in higher education. It examines the practice and process of peer observation as a professional development tool for academics teaching in higher education; looking at whether it enhances and facilitates collegiate relationships and self-reflection, which in turn leads to enhanced teaching, learning, and assessment practices. This scoping review focuses on the use of peer observations, rather than peer evaluations, the distinction between these approaches hinges on the difference between the ethos of the process. Peer observation is voluntary, confidential, and bidirectional (i.e. situated peer observation) between the peer observers and observee. Hence the review is bounded by a definition of peer observation of teaching (POT) as a formative professional development tool reliant on the participants voluntarily engaging in the process with the explicit purpose of advancing their professional practice. Unlike peer evaluations and reviews where the feedback is used to evaluate practice, peer observation of teaching is a process that is most successful when pursued as part of a collaborative, voluntary professional development programme that encourages ongoing dialogue among teaching professionals.