In jazz, swing was gradually being replaced by bebop. Dizzy Gillespie, a trumpeter and one of the originators of bop, wrote three arrangements for Woody Herman, "Woody'n You", "Swing Shift" and "Down Under". These were arranged in 1942. "Woody'n You" was not used at the time. "Down Under" was recorded July 24, 1942. The fact that Herman commissioned Gillespie to write arrangements for the band and that Herman hired Ralph Burns as a staff arranger, heralded a change in the style of music the band was playing.