The Second Viennese School (German: Zweite Wiener Schule, Neue Wiener Schule) is the group of composers that comprised Arnold Schoenberg and his pupils and close associates in early 20th century Vienna; where he lived and taught, sporadically, between 1903 and 1925. Their music was initially characterized by late-Romantic expanded tonality and later, following Schoenberg's own evolution, a totally chromatic expressionism without firm tonal centre, often referred to as atonality; and later still, Schoenberg's serial twelve-tone technique. Though this common development took place, it neither followed a common time-line nor a cooperative path. Likewise, it was not a direct result of Schoenberg's teaching—which, as his various published textbooks demonstrate, was highly traditional and conservative. Schoenberg's textbooks also reveal that the Second Viennese School spawned not from the development of his serial method, but rather from the influence of his creative example.
The principal members of the school, besides Schoenberg, were Alban Berg and Anton Webern, who were among his first composition pupils. Both of them had already produced copious and talented music in a late Romantic idiom but felt they gained new direction and discipline from Schoenberg's teaching. Other pupils of this generation included Ernst Krenek, Heinrich Jalowetz, Erwin Stein and Egon Wellesz, and somewhat later Eduard Steuermann, Hanns Eisler, Roberto Gerhard, Norbert von Hannenheim, Rudolf Kolisch, Paul A. Pisk, Karl Rankl, Josef Rufer, Nikos Skalkottas, Viktor Ullmann, and Winfried Zillig. Though Berg and Webern both followed Schoenberg into total chromaticism and both adopted twelve-tone technique soon after he did, each in his own way, not all of these other pupils did so, or waited for a considerable time before following suit. Schoenberg's brother-in-law Alexander Zemlinsky is sometimes included as part of the Second Viennese School, though he was never Schoenberg's pupil and never renounced a traditional conception of tonality. Several yet later pupils, such as Zillig, the Catalan Gerhard, the Transylvanian Hannenheim and the Greek Skalkottas, are sometimes covered by the term, though (apart from Gerhard) they never studied in Vienna but as part of Schoenberg's masterclass in Berlin. Membership in the school is not generally extended to Schoenberg's many pupils in the United States from 1933, such as John Cage, Leon Kirchner and Gerald Strang, nor to many other composers who, at a greater remove, wrote compositions evocative of the Second Viennese style, such as the Canadian pianist Glenn Gould. By extension, however, certain pupils of Schoenberg's pupils, such as Berg's pupil Hans Erich Apostel and Webern's pupils René Leibowitz, Leopold Spinner and Ludwig Zenk, are usually included in the roll-call.