Heather Mary Harper was a Northern Irish operatic soprano. She was active internationally in both opera and concert. She performed roles such as Helena in Benjamin Britten's A Midsummer Night's Dream at the Royal Opera House, Elsa in Wagner's Lohengrin at the Bayreuth Festival, and the Countess in Mozart's The Marriage of Figaro at the Metropolitan Opera. She became known internationally when she stepped in for the world premiere of Britten's War Requiem in 1962, and remained associated with the composer's work, but also sang other premieres.