The Rake"s Progress is Stravinsky"s biggest work and one of the few great operas written since the 1920s, rare too for the unusual quality of its libretto, by Auden and Kallman. Its importance is undisputed, but so too are the problems it raises: problems of both performance and understanding, caused by the irony with which it is so thoroughly permeated. In aspects of style and operatic convention it looks back to the eighteenth century, and in particular to the operas of Mozart and da Ponte, while making references also to other periods, to operas from Monteverdi to Verdi. Yet at the same time it is wholly a work of the twentieth-century, and indeed it is centrally concerned with the impossibility of return, artistic, psychological or actual, as well as with the nature and limitation of human free will. The Rake"s Progress is not one of unbridled dissipation but rather, more interestingly, one of attachment to naive notions of freedom and choice, and his tragedy is that he can never go back.