At the beginning of the Roman Principate, there was no self-evident model for the residence of the Roman emperor. During a long period of experimentation, emperors and their architects attempted to fashion spaces appropriate to the social rituals of their courts and to the self-image they aimed to project. By the end of the first century, a viable palace model was established in Rome, and elements of this were then redeployed in the palaces of the Tetrarchic period. This chapter presents a selection of literary sources, archaeological plans, photographs, and computer visualizations to illustrate the developing Roman palace model, its Hellenistic forerunners, and its afterlife in the Tetrarchic period. It also contains a selection of sources relating to imperial villas in Italy for which there are archaeological remains. This collection shows that imperial villas did share some common features, even if a clear ‘imperial villa model’ never developed.