Clemens Heinrich Krauss was an Austrian conductor, opera impresario and eventually librettist, associated with Wagner, Mozart and particularly the music of Richard Strauss.
Krauss made the rounds of regional centers, conducting in Riga (1913-1914), Nuremberg (1915) and Stettin (1916-1921) (formerly part of Pomerania in Germany; now part of Poland). The latter appointment gave him ample opportunity to travel to Berlin to hear Arthur Nikisch conduct the Berlin Philharmonic, a major influence. He then returned to Austria as director of the opera and symphony concerts in Graz. In 1922, he joined the conducting staff of the Vienna State Opera and teacher of the conducting class in the Vienna Singakademie. He conducted the Vienna Tonkünstler concerts from 1923 to 1927, and was Intendant of the opera in Frankfurt and director of the Museum concerts there from 1924 to 1929.
He guest-conducted in the United States in 1929, with the Philadelphia Orchestra and New York Philharmonic. Also in 1929, he was appointed director of the Vienna State Opera. Its orchestra, which was part of the independent concert entity known as the Vienna Philharmonic, appointed him its music director in 1930. He was a regular conductor at the Salzburg Festival from 1926 to 1934, where in 1930 he conducted Alban Berg's avant-garde atonal opera Wozzeck.
Krauss gave up his Vienna positions in 1933-34 to direct the Berlin State Opera in 1935 after Erich Kleiber had resigned in protest against Nazi policies. In 1933, he took over the preparations for the premieres of Richard Strauss's opera Arabella after the departure of conductor Fritz Busch (another non-Jewish anti-Nazi). Krauss's own position on Nazism was unclear, although he did enjoy a close relationship with Nazi official Alfred Frauenfeldand and it has been claimed that he sought out the Nazi Party membership in 1933. In 1937, he was appointed Intendant of the National Theatre Munich following Hans Knappertsbusch's resignation. He became a close friend of Strauss, and even wrote the libretto for his opera Capriccio which he premiered in Munich in 1942. He also conducted the premieres of Strauss's operas Friedenstag and Die Liebe der Danae. 
After the Munich Opera House had been destroyed by Allied bombing, Krauss returned to conduct the Vienna Philharmonic in 1944-45 until it ceased activities shortly before the end of World War II. After the war, Allied officials investigated his career and forbade him from appearing in public until 1947, when it emerged that he had helped Jews escape from the Third Reich. Krauss then resumed conducting many of the Vienna Philharmonic's concerts.
He conducted opera at Covent Garden in London starting in 1951, and at the 1953 Bayreuth Festival (including an impressive Der Ring des Nibelungen cycle starring Astrid Varnay as Brunnhilde). 
He died in 1954 while on tour with the Vienna Philharmonic in Mexico City, and is buried alongside his wife, singer Viorica Ursuleac, who died in 1985, in Ehrwald, Austria.