Philip Anthony Treacy (born 26 May 1967) is an award–winning Irish haute couture milliner, or hat–designer, based in London, who has been described by Vogue magazine as "perhaps the greatest living milliner".
In 2000, Treacy became the first milliner in 80 years to be invited to exhibit at the Paris haute couture shows.
Treacy has been associated with some of the largest fashion houses and particularly Chanel and Givenchy, as well as celebrities such as Isabella Blow, Lady Gaga, Madonna and Sarah Jessica Parker.
Treacy has been associated with British royalty, and has designed hats for royal occasions.