This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book provides a conspectus of the state of Cavalli research in the twenty-first century. It offers completely new material and well-known material in completely new directions. The book also offers a good sense of the kinds of documentary information available to the Cavalli researcher. It illuminates the vicissitudes involved in transferring an opera from the page to the stage. The book explores the transformation of the myth of Jason and the Golden Fleece, on the larger European stage as well as within the more localized traditions of seventeenth-century Venetian theater. It focuses on a relatively understudied subject within research on the Venetian libretto—namely, its links to Spanish Golden Age drama. The book provides a methodological model for studying the dissemination patterns of a Venetian opera.