Exploring the work of the major nineteenth-century French poet Charles Baudelaire (1821–67), this book examines how and why Baudelaire’s poetry has inspired so many composers to set it to music in different ways. The author proposes a new model for analysing song, through an ‘assemblage’ approach, which examines the complex relationships formed between common features of poetry and music, including metre/prosody, form/structure, sound properties/repetition, and semantics. The model also factors in the realities of song as a live performance genre, revealing which parameters of song emerge as standard for French text-setting and where composers diverge in their approach. The specific case studies that make up the second half of the book focus on Baudelaire song sets produced by European composers between 1880 and 1930, specifically Maurice Rollinat, Gustave Charpentier, Alexander Gretchaninov, Louis Vierne, and Alban Berg. Using this corpus, the assemblage model is tested to uncover new findings about what happens to Baudelaire’s poetry when it is set to music. Analysing Baudelaire’s poetry within song settings uncovers richer features of the texts that we might otherwise not see or hear. Examining each song setting in close detail confirms that there are no overt resonances between the types of poems selected for musical interpretation, just as there is no single, perfect ‘ideal’ setting of Baudelaire.