Taking the Piazza San Pietro as a point of departure, this article explores the possible relationship between performativity and Baroque architecture. Can the concept of performativity serve as a useful tool for the interpretation of Baroque space? Can it contribute to our understanding of the architectural discourse in the seventeenth century? A hypothesis is that the interpretative strategies enabled by the concept of performativity bear some affinity to the ways in which architecture was experienced, conceived of, and theorized in the seventeenth century.