Part I: The seventeenth and eighteenth centuries. Pre-operatic forms ; First operatic forms ; Formalisation ; Reform: the reintegration of elements ; Comedy and the 'real world' ; Authentic performance -- Part II: The nineteenth century. Romanticism and Romantic opera in Germany ; Opera in nineteenth-century Italy ; Grand opera and the visual language of opera ; The Wagnerian revolution ; Nationalists: vernacular language and music ; The role of the singer -- Part III: The twentieth and twenty-first centuries. The turn of the century and the crisis in opera ; First modernism: symbolist and expressionist opera ; The dramaturgy of opera: libretto-words and structures ; Narrative opera: realist and non-realistic ; Radical narratives ; Directors and the direction of opera.