The composer's three first impromptus were published during his lifetime: Opus 29 in December 1837, Opus 36 in May 1840, and Opus 51 in February 1843. The fourth impromptu ("Fantaisie-Impromptu"), Op. 66, is a posthumous publication.

James Huneker wrote: "The A flat Impromptu, op. 29, is, if one is pinned down to the title, the happiest named of the set. Its seething, prankish, nimble, bubbling quality is indicated from the start; the D natural in the treble against the C and E flat--the dominant--in the bass is a most original effect, and the flowing triplets of the first part of this piece give a ductile, gracious, high-bred character to it. The chromatic involutions are many and interesting. When the F minor part is reached the ear experiences the relief of a strongly contrasted rhythm. The simple duple measure, so naturally ornamented, is nobly, broadly melodious. After the return of the first dimpling theme there is a short coda, a chiaroscura, and then with a few chords the composition goes to rest. A bird flew that way!"

Niecks: "How Chopin produced the "Impromptu opus. 29 I do not know. Although an admired improviser, the process of composition was to him neither easy nor quick. But be this as it may, this impromptu has quite the air of a spontaneous, unconstrained outpouring. The first section with its triplets bubbles forth and sparkles like a fountain on which the sunbeams that steal through the interstices of the overhanging foliage are playing. The F minor section is sung out clearly and heartily, with graces beautiful as nature's. The song over, our attention is again attracted by the harmonious murmuring and the changing lights of the water."

Kleczynski says, "Here everything totters from foundation to summit, and everything is, nevertheless, so beautiful and so clear."