American oboist Gail Hennessy was born in Wisconsin, and studied modern oboe in Louisville, Kentucky 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 has also been influenced by playing in masterclasses given by the Dutch oboist Ku Ebbinge and Michel Piguet of Switzerland.
She now regularly plays and records with many of Britain's early music groups including the Hanover Band, Parley of Instruments, New London Consort, St James’s Baroque Players, Ex Cathedra, the London Oboe Band, and her own group, Musetta, and has also played for Les Arts Florissants, Anima Eterma, the Gabrieli Players, the English Concert and the Academy of Ancient Music.
Gail 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.