Starting with Popper, social theorists across the board have acknowledged that traditions serve socially valuable functions. However, while traditions are usually understood as ‘living’ entities that come in overlapping varieties and evolve over time, the socially valuable functions attributed to tradition tend to presuppose invariability in ways of thinking and acting. Addressing this tension, this article provides a detailed analysis of the concept of tradition, and directs special attention to conceivable criteria for the authentic continuation of a tradition. It is argued that the ways of thinking and acting that constitute the material of a tradition must – among faithful members of that tradition – stand in a relation of equivalence – not identity or similarity. The implications of this account concern our ability to decide (normatively) conflicts over authenticity among rival tradition branches as well as the role that traditions play in policy-making.