In this book, Philip Kiernan explores how cult images functioned in Roman temples from the Iron Age to Late Antiquity in the Roman west. He demonstrates how and why a temple's idols, were more important to ritual than other images such as votive offerings and decorative sculpture. These idols were seen by many to be divine and possessed of agency. They were, thus, the primary focus of worship. Aided by cross-cultural comparative material, Kiernan's study brings a biographical approach to explore the 'lives' of idols and cult images - how they were created, housed in temples, used and worshipped, and eventually destroyed or buried. He also shows how the status of cult images could change, how new idols and other cult images were being continuously created, and how, in each phase of their lives, we find evidence for the significant power of idols.