According to the paper, she leaves after a period of financial troubles and rumors of power struggles at the festival.
"I feel there is a move towards a more populist festival, so I feel it's time to move on," Miller told the Scotsman. "I get passionate about the music that is moving the genre forward, rather than looking for more accessible music that will neither frighten people nor stimulate them."
Stuart Gulliver, the chairman of the festival's board, said, "We are sorry to hear that Olive Millen has decided to retire from the jazz business. In any arts organization, there will always be tension between commerciality and artistic content. However, the board is clear and confident in the direction the festival is taking."
Founded in 1987, the festival has presented such jazz stars as Dizzy Gillespie, Ray Charles, and Miles Davis. This year's event included visits from saxophonist Michael Brecker and bassist Avishai Cohen, as well as pop star Van Morrison.