The collection Modern Piano Works by Universal Edition, planned for publication in 1928, was initially intended to include the first of Schoenberg's Three Piano Pieces, Op. 11 (1909). However, he decided to compose a new piano piece for the collection, and thus this work was composed between December 1928 and April of the following year, 1929. Although a very short work, lasting less than three minutes, it is written based on sonata form.

  Schoenberg composed Op. 33a using the twelve-tone technique, similar to his Five Piano Pieces, Op. 23 (1920–23), and Piano Suite, Op. 25 (1921–23). In this work, only a limited set of four row forms are used: the prime form, its inversion transposed up a major third, and their respective retrogrades. In the opening 24 measures, which constitute the exposition of the sonata form, two themes based on the same row are presented in different guises. The first theme consists of a succession of three four-note chords, derived sequentially from the beginning of the row. In contrast, the second theme (from m. 14) presents six-note row segments, divided into two halves from the two basic row forms, both melodically and concurrently. Although the development section is short, its first half features elements of the second theme, while the second half (from m. 25) shows elements of the first theme. The dynamics also reach their peak with a fortississimo, marking the climax of the piece. In the recapitulation following the fermata (from m. 32), the two themes reappear in slightly altered forms, leading to a coda (from m. 37) based on the harmonically distinctive first theme.

  In the attempt to compose based on sonata form and with limited material, one can discern the influence of Classical and Romantic works that Schoenberg himself thoroughly analyzed. This work, composed using the twelve-tone technique while incorporating the forms and styles of traditional works, can be positioned as an important stage in the development of Schoenberg's compositional method.