We contend that the notion of critical friend is a legitimate consideration with respect to considering how to most effectively encourage professional relationships that support and enhance professional learning and development (PLD). This paper will firstly consider an overarching framework of professional relationships and define characteristics, roles and expected tasks of a critical friend, noting that the development of trust is central to both. The authors thread (where relevant) elements of PLD throughout the framework, before introducing the reader to a proposed dual-continuum model of critical friend roles and tasks in PLD. A scenario is then mapped for each of the four quadrants, displaying elements of a specific type of critical friend activity related to the defining characteristics of critical friend shared in the paper. The intention is to capture the nuances between multiple enactments of critical friend as well as informing a possible continuum of what constitutes operating as a critical friend supporting and enhancing PLD. The paper concludes with observations from the scenarios and future considerations for further exploration of critical friend roles, tasks, skills and behaviour.