Dag Achatz is a Swedish virtuoso pianist and composer. His recording for BIS of his own transcription, for piano 2 hands, of Stravinsky's Rite of Spring is widely acknowledged to be one of the great recordings of the 20th century. Leonard Bernstein asked him to transcribe his ballet, Fancy Free, which Achatz then recorded along with his own transcription of Bernstein's Symphonic Danses from West Side Story.