The introduction to this volume sets out some of the challenges in defining and using the term ‘decadence’ to describe the literature covered by the chapters that follow. It begins by establishing the patterns for conservative dismissals of Decadent literature in responses to the Pre-Raphaelite poets in the 1870s, before turning to the hysteric anti-Decadent critique of Max Nordau. In opposition to these challenges to ‘decadence’ it surveys some of the most important attempts to define a literature of Decadence: Gautier, Bourget, and Arthur Symons. What emerges is an understanding of Decadence as another name not for cultural decline and dissipation, but for aesthetic and cultural revolution. The chapter then examines how Decadent studies has in recent years undergone a series of transformations, encouraging us to interrogate the gendered, temporal, formal, political and geographical frameworks that had governed earlier understandings of Decadence as a literary practice in Britain.