Hilary Erhard Duff (born September 28, 1987) is an American actress, pop singer/songwriter and entrepreneur. She has an elder sister, Haylie Duff, who is also an actress/singer.

After gaining fame for her starring role on the television show Lizzie McGuire, Duff went on to have a film career, and her most commercially successful pictures include Cheaper by the Dozen (2003), The Lizzie McGuire Movie (2003), and A Cinderella Story (2004). She reportedly earned $15 million in 2005.[1] Duff has expanded her repertoire into pop music, with three RIAA certified-platinum albums and over thirteen million albums sold worldwide,[2] and she has launched a clothing line, Stuff by Hilary Duff, and an exclusive perfume with Elizabeth Arden. Duff and her mother were listed as producers for the movie Material Girls,[3] and she will soon produce her sister's debut album.[4]
Her upcoming films include the 2007 action thriller War, Inc., animated comedy Foodfight! and independent films "Greta" and "Safety Glass".[5] Duff's latest studio album, Dignity, was released in April 2007 and has sold 840,000+ since then.