The composition begins with a lengthy and rhythmically free introductory section, during which essential thematic materials are stated. A steady rhythmic pulse then signals the start of the actual "Song", during which the soloist presents several haunting melodic lines. As the work unfolds, thematic materials from the introduction return, and during the concluding section, the two primary melodic lines of the Song are combined in a duo between the euphonium and a string-like synthesizer voice created with an analog synthesizer. The coda, an ethereal variant of the introduction, eventually fades away into nothing.
Night Song was originally created specifically as a euphonium solo in 1989, but by virtue of some minor adaptations made by the composer in 2021, it is now equally well-suited as an expressive vehicle for the French Horn. Both euphonium and horn parts are provided.