Gail Hennessy was born in Wisconsin in the USA, and studied modern oboe at the University of Louisville and Historical Performance Practice at Washington University before travelling to Britain in 1982, where she studied baroque oboe with the late David Reichenberg, and was an apprentice to baroque oboe maker Mary Kirkpatrick. She now regularly plays and records with many of Britain's early music groups, as well as appearing as a soloist and chamber musician around the world. She teaches baroque oboe at the Guildhall School of Music and Drama in London, at Birmingham Conservatoire, at the Dartington International Summer School and at the Cambridge Early Music Summer Schools.