In classical Latin, luxuria means ‘desire for luxury’; it is linked with the ideas of excess and deviation from a standard, and in most cases labelled as a vice which contrasts with the innate frugal nature of the Romans. Indeed, Latin authors see it not as endemic, but as an import from the East in the aftermath of military conquests, and as a cause of fatal decline. After dealing with etymological and semantic issues, the book discusses the influence of Greek culture on the Roman concept and the peculiar characteristics of Roman luxuria. Roman views on luxuria are analysed through close readings of selected passages, in their historical evolution from Cato the Elder, who regards it as the opposite of the ideal way of life of the Romans, to the Christian poet Prudentius, who represents it in an allegorical fight with Sobriety. Attention is paid both to single authors and to literary genres, such as historiography and satire. Particular consideration is given to the rhetorical device of personification, which can be traced from the first appearances of luxuria in Latin literature to the ones in late antiquity. Much space is devoted to Seneca the Younger, whose work is very much concerned with this passion, and who both defends himself from the charge of luxuria and violently attacks it in others, describing it as the archenemy of philosophical life. Along the centuries, the focus of this vice shifts from the economic sphere, and the idea of the waste of money, to the erotic one, to the point that in the Christian world luxuria becomes one of the Seven Capital Sins, representing the vice of lust.