Chapter One provides an in-depth introduction to somaesthetics as a methodological practice for Renaissance Art History and outlines the aims and content of the book. The chapter defines somaesthetic inquiry in relation to Medieval and Renaissance scholarship on the body, ritual, performance, and viewership, and advocates for a performative approach to the analysis of Renaissance art. Considering the dynamics of works of art that activate and emplace their viewers, the chapter explores the theoretical implications of considering Renaissance viewers as critical technologies in the rise and sustenance of power in Medicean Florence.