Die glückliche Hand (The Lucky Hand, 1909–1913), Op. 18, is a four-scene opera or "Drama with Music in One Act" by Arnold Schoenberg to his own libretto. Like Erwartung (Expectation, 1909), it drew on Otto Weininger's book Sex and Character and reflected Schoenberg's own life, perhaps including his sense of artistic mission, audience reception, wife's affair, or some combination. It conveys the idea that man repeats his mistakes. The Vienna Volksoper premiered it on 24 October 1924.

Erwartung (Expectation), Op. 17, is a one-act monodrama in four scenes by Arnold Schoenberg to a libretto by Marie Pappenheim. Composed in 1909, it was not premiered until 6 June 1924 in Prague conducted by Alexander Zemlinsky with Marie Gutheil-Schoder as the soprano. The opera takes the unusual form of a monologue for solo soprano accompanied by a large orchestra. In performance, it lasts for about half an hour. It is sometimes paired with Béla Bartók's opera Bluebeard's Castle (1911), as the two works were roughly contemporary and share similar psychological themes. Schoenberg described Erwartung, saying "the aim is to represent in slow motion everything that occurs during a single second of maximum spiritual excitement, stretching it out to half an hour." Philip Friedheim has described Erwartung as Schoenberg's "only lengthy work in an athematic style", where no musical material returns once stated over the course of 426 measures. In his analysis of the structure, one indication of the complexity of the music is that the first scene of over 30 bars contains 9 meter changes and 16 tempo changes. Herbert Buchanan has countered this description of the work as "athematic", and the general impression of it as "atonal", in his own analysis. The musicologist Charles Rosen has said that Erwartung, along with Berg's Wozzeck and Stravinsky's The Rite of Spring, is among the "impregnable" "great monuments of modernism." According to Christopher Small, "Schoenberg's intuitive understanding of the integrative process of dreams is revealed especially in the marvellous closing pages, filled as they are with tenderness and longing. At the end we can almost see the sleeper awake as with a scurry of chromatic scales the music vanished from our hearing and the dream recedes from her waking mind."

Moses und Aron (English: Moses and Aaron) is a three-act opera by Arnold Schoenberg with the music to the third act unfinished. The German libretto is by the composer. It is based on selected incidents from the Book of Exodus (chapters 3-32).

In music, the "Ode-to-Napoleon" hexachord (also magic hexachord, hexatonic collection, or hexatonic set class) is the hexachord named after its use in the twelve-tone piece Ode to Napoleon Buonaparte Op. 41 (1942) by Arnold Schoenberg (setting a text by Byron). Containing the pitch classes 014589 (C, D♭, E, F, G♯, A), it is given Forte number 6–20 in Allen Forte's taxonomic system. The primary form of the tone row used in the Ode allows the triads of G minor, E♭ minor, and B minor to easily appear. The "Ode-to-Napoleon" hexachord is the six-member set-class with the highest number of interval classes 3 and 4 yet lacks 2s and 6s. 6-20 maps onto itself under transposition three times (@0,4,8) and under inversion three times (@1,4,9) (six degrees of symmetry), allowing only four distinct forms, one form overlapping with another by way of an augmented triad or not at all, and two augmented triads exhaust the set as do six minor and major triads with roots along the augmented triad. Its only five-note subset is 5-21 (0,1,4,5,8), the complement of which is 7-21 (0,1,2,4,5,8,9), the only superset of 6-20. The only more redundant hexachord is 6-35. It is also Ernő Lendvai's "1:3 Model" scale and one of Milton Babbitt's six all-combinatorial hexachord "source sets". The hexachord has been used by composers including Bruno Maderna and Luigi Nono, such as in Nono's Variazioni canoniche sulla serie dell'op. 41 di Arnold Schönberg (1950), Webern's Concerto, Op. 24, Schoenberg's Suite, Op. 29 (1926), Babbitt's Composition for Twelve Instruments (1948) and Composition for Four Instruments (1948) third and fourth movements. The hexachord has also been used by Alexander Scriabin and Béla Bartók. It is used combinatorially in Schoenberg's Suite: P3: E♭ G F♯ B♭ D B // C A A♭ E F D♭ I8: G♯ E F D♭ A C // B D E♭ G F♯ B♭ Note that its complement is also 6-20.

Dreimal sieben Gedichte aus Albert Girauds "Pierrot lunaire" ("Three times Seven Poems from Albert Giraud's 'Pierrot lunaire'"), commonly known simply as Pierrot lunaire, Op. 21 ("Moonstruck Pierrot" or "Pierrot in the Moonlight"), is a melodrama by Arnold Schoenberg. It is a setting of 21 selected poems from Albert Giraud's cycle of the same name as translated into German by Otto Erich Hartleben. The work is written for reciter (voice-type unspecified in the score, but traditionally performed by a soprano) who delivers the poems in the Sprechstimme style accompanied by a small instrumental ensemble. Schoenberg had previously used a combination of spoken text with instrumental accompaniment, called "melodrama", in the summer-wind narrative of the Gurre-Lieder, which was a fashionable musical style popular at the end of the nineteenth century. Though the music is atonal, it does not employ Schoenberg's twelve-tone technique, which he did not use until 1921. Pierrot lunaire is among Schoenberg's most celebrated and frequently performed works. Its instrumentation – flute, clarinet, violin, cello, and piano with standard doublings and in this case with the addition of a vocalist – is an important ensemble in 20th- and 21st-century classical music and is referred to as a Pierrot ensemble. The piece was premiered at the Berlin Choralion-Saal on October 16, 1912, with Albertine Zehme as the vocalist. A typical performance lasts about 35 to 40 minutes. The American premiere took place at the Klaw Theatre, on Broadway, New York, on 4 February 1923 as part of a series of concerts organised by the International Composers' Guild.