The Sinfonietta features Roussel's typical three movements in fast- slow-fast format, but the central movement is shorter than sometimes. Instead of the quiet contemplation of the Concert pour petit orchestre, the Andante of the Sinfonietta contains anguish and anger. Perhaps it is significant that Roussel was recuperating from a serious bout of pneumonia when he wrote the Sinfonietta; and here, with death so close, he was fighting against it in his music.

As is the case in other pieces when a slow movement deals with death (Suite in f#, Concerto for piano, Concertino for cello), Roussel follows the anguished slow movement with a vigorous reaffirmation of life.

The ascetic exercise is here pushed to its limit: a condensed symphony which hardly uses any counterpoint as in the universe of the string quartet or Third Symphony. It seems that the playful composer is winking at us at every bar; integrating styles of writing and developments taken from Beethoven, Brahms or Franck. [Damien Top]

Once again we find clarity of form, rhythmical energy and meticulous composition exploiting clearly-stated ideas in a very personal manner; in short, that original style of writing, bold and richly polyphonic... which defines Roussel as a link between d'Indy and Debussy. The strictness of the one, the fantasy of the other: it is Roussel's fusion of these two opposites that assures him lasting fame in the history of music. [Georges Beck]

One of the most appealing compositions of the composer. Music concentrated in scope, as precise as the jeweled works in a woman's wrist watch. It sounds as it appears on the score page — clear, of pellucid definition as though all sounds, rhythms, and phrases were made with a ruler. [Arthur Cohn]