Ibert refused to ally himself to any particular musical fashion or school, maintaining that "all systems are valid", a position that has caused many commentators to categorise him as "eclectic". His biographer, Alexandra Laederich, writes, "His music can be festive and gay … lyrical and inspired, or descriptive and evocative … often tinged with gentle humour … all the elements of his musical language bar that of harmony relate closely to the Classical tradition." The early orchestral works, such as "Escales", are in "a lush Impressionist style", but Ibert is at least as well known for lighthearted, even frivolous, pieces, among which are the "Divertissement" for small orchestra and the Flute Concerto.