This chapter presents a review of a research corpus of 350 years of silhouettes in Western fashion, mapping how the transformation in the relation between the body and the corset is an emblematic case of the semantic mechanism of fashion change. The section starts by establishing the body and dress as material “anatomies”, which contain the clues for the construction of the same entities as subjects or agents of fashion. The in-depth examination of the materials of the body and dress results in the semiotic definition of the expected functions of these agents, which are analysed as the “programmes” of body and dress. Following Landowski’s schema of perilous interactions, these relations are expanded into other modes of interaction—adjustment, accident, and manipulation—and how these regimes govern dynamics other than the “programmed use” of body, dress, and fashion. The section closes with the modal confrontations between Body and Dress as an engine of conflict or friction that forces fashion to change.