Running throughout the work of Oliver O’Donovan is a discussion of the nature of authority, and its relation to reality, and to freedom. While holding fast to the maxim that authority is the correlate of freedom, O’Donovan’s understanding of authority moves, as a result of his engagement with the nature of political authority, to emphasise the idea of social mediation. This leads, in the most recent works, to a description of authority as an event in which reality is disclosed. Arguably, this formal account does not adequately distinguish the element of practical direction within authority, meaning that it may struggle to explain some ways in which we speak about authority’s presence, and its misuse. However, there may be resources for making this distinction within O’Donovan’s understanding of judgment as an act of moral discrimination with a twofold form. O’Donovan’s is an elegant and economical account of authority, promising to provide a simple analysis that encompasses the peculiarities of authority and illuminates a wide range of phenomena.