She was the opening act for Jimmy Page and Robert Plant, Sting, and George Clinton and The P-Funk Allstars and has collaborated with Roger Waters, Hans Zimmer, Josh Groban, Herbie Hancock, B.

[5][6] After graduating from Brown University with a BA in political science, Haydn started composing original songs and became one of the most requested session violinists around Los Angeles.

In 1983, she starred as Belinda Capuletti, the smart and sassy daughter of Rodney Dangerfield's character in the comedy film Easy Money.

[4] By the time she signed with Atlantic in 1997 and released her debut album, Lili, she had embraced a variety of genres, having played with Quwaali musician Nusrat Fateh Ali Khan, Porno for Pyros, Tracy Chapman, The Jayhawks, Brandy, Tony!

In addition, she has played with, sung with, and opened for Sting, Josh Groban, Herbie Hancock, Jimmy Page and Robert Plant, Matchbox 20, Seal, and George Clinton, who calls her "the Jimi Hendrix of the violin".

For the next five years, she continued working on film scores and composed music for her fourth album, Lililand, released in September 2014.

[2] Since the release of Lililand in 2014, Haydn has scored seven films, including Academy Award winner Freida Mock's Anita, The House that Jack Built, and Sundance Selects' Driver X.

In 2018, Haydn joined with musicians Hamid Saeidi, MB Gordy, and Itai Disraeli to create the group Opium Moon.

Her song "Unfolding Grace" appears on a CD compilation with U2 and Sting which benefits Aung San Suu Kyi and the Burmese pro-democracy movement.