Following his English edition of Alma Mahler-Werfel's Diaries 1898-1902, Antony Beaumont presents both the first comprehensive biography of the composer and conductor Alexander Zemlinsky (1871-1942) and a critical assessment of his works. "Zemlinsky-all hail to you!" wrote the young Alma. "All hail to you and your art." When she first met him, Zemlinsky was the most promising Viennese composer of his generation. In 1901, when Alma abruptly ended their passionate love affair in order to marry Gustav Mahler, the crisis served to transform Zemlinsky's talent into mastery. Only long after his death, however, did his music begin to receive its due. Zemlinsky was central to the musical life of Vienna and Central Europe, and this brilliant biography illuminates a social and cultural milieu that disappeared forever with the triumph of Hitler's Reich. Beaumont details the composer's early years as a protege of Brahms and Mahler, his complex friendship with his brother-in-law Arnold Schoenberg, the influence of his teaching on the boy-prodigy Erich Korngold, his kindly and helpful attitude toward the hypersensitive Anton Webern, and his heartfelt friendship with Alban Berg. Zemlinsky was one of the leading conductors of the interwar period, considered by both Schoenberg and Stravinsky the finest they had ever heard. Beaumont charts Zemlinsky's career from Vienna to Berlin, St. Petersburg, and Prague, providing insight into his Catholic-Sephardic background and investigating his keen interest in esoteric aspects of music, including color symbolism and numerology. The author's analyses of Zemlinsky's major scores are accessible and fully contextualized.