Alasdair MacIntyre's argument, that teaching is not a social practice, has been extensively criticised, and indeed teaching is normally understood more generally to be a form of generic activity that is a practice in its own right. His associated proposition, that teachers are practitioners of the discipline they teach, has, however, received considerably less attention. MacIntyre himself recognised that for teachers to be understood as being part of the discipline they teach, a broader definition of what is meant by ‘discipline’ would be required. In order to achieve this, it is necessary to make a distinction between a ‘discipline’ and a ‘profession’ and not to conflate the practice of the discipline with the practice of professional academics. Such a distinction makes it possible to argue that teachers are engaged in the practice of the discipline they teach. As recent developments in social epistemology and the sociology of knowledge have suggested, it is indeed not just possible, but arguably necessary, to understand teachers in these terms. In seeking to understand what it means to be a teacher, there is thus much to be gained from further reflection as to the relationship between a teacher and his or her academic discipline. The reconsideration of this relationship might well cause us to challenge the idea that teaching is a form of generic activity.