Prélude à l'après-midi d'un faune by Claude Debussy (1862–1918) is widely considered the first work of modern music, bringing the long nineteenth century dominated by Austrian and German classic and romantic composers to an end. Faune is Debussy's first major orchestral composition and was seminal in propelling his young career forward.

Its impact on orchestral timbre, combined with the composer's fusion of the poetic with abstract music, is unique, as Pierre Boulez noted: “The writing for woodwinds and brasses, incomparably light-handed, performed a miracle of proportion, balance, and transparency.” It would not be an overstatement to assert that in another modern classic, namely Igor Stravinsky's Le sacre du printemps, the opening with its high bassoon weaving a pagan spell is allied with Debussy's Faune with its sultry flute opening. Indeed it is this opening that apparently so captivated listeners at the first performance and was recounted by the conductor at the premiere, Gustave Doret: “I wait a long moment after having imposed silence on the last lingering conversations among the audience. The hall is full. An imposing silence reigns when our marvelous flautist Barrère unrolls his opening theme. ... Suddenly I feel behind my back ... a completely captivated public!”

Stéphane Mallarmé (1842–1898), whose poem L'après-midi d'un faune (1876) was the catalyst for Prélude à l'après-midi d'un faune, was a symbolist poet. Mallarmé's work mesmerized Debussy years before the two were to meet and become friends; Both were avid Wagnerians, with Debussy influenced and inspired by poetry, and Mallarmé enamored by music and the "protective mystery of its notation."

Mallarmé was convinced that Faune should be staged and with the poet and composer being well acquainted in the early 1890s, one would assume that they exchanged ideas on a musical and theatrical depiction of the work. A collaboration on Prélude à l'après-midi d'un faune between Debussy, Mallarmé and Paul Fort was to be presented at the Theâtre d'art on 27 February 1891; this performance however never took place.

Mallarmé's words gave Debussy the impetus to create a "tone poem," characterizing its "atmosphere" in music — setting it as it were without being so explicit that he needed to follow the exact words of the poem. Instead, Debussy strove to paint the seductive nature of the poem in sound.

The actual work of composing must have begun in 1891 or earlier, as the autograph full score carries the date 1892 on the title page, which must be understood to represent the beginning; the date 1894 on the final page must refer to the work's completion. The output from this first major phase of Debussy's composing career is perhaps only exceeded by the "middle" period between 1903–09 which then firmly placed the composer as a major figure not only in the flourishing Parisian music world, but also internationally.

Notes by Douglas Woodfull-Harris as they appear in introduction of the orchestral score published by Bärenreiter-Verlag, Kassel, 2011