Drawing on the textual residue of one town's pervasive orality and the written traces left by its sophisticated forms of symbolic communication, this chapter shows that a medieval community could create a public sphere. In the twelfth and thirteenth centuries, Arras was one of the wealthiest, most populous, and most influential towns of northern Europe. It was also one of the most contested, and is frequently cited as the paradigm of medieval urban complexity, externally and internally. In Arras and the other crowded mercantile towns along the Franco-Flemish border, the habit of keeping track of things was already well-established and common in every sense of the word. In 1175, Arras became one of the first communes in northern Europe to possess and use a seal, a symbolic tool that was increasingly necessary for participation in trade, governance, and diplomacy, and which in turn authenticated the documents that furnished proofs of a town's independence.