Ann has established close links with both English National Opera and the Royal Opera House, Covent Garden

She was born in Dublin and studied with Frederick Cox at the Royal Manchester College of Music (now the Royal Northern College of Music). She has sung the title roles in Handel's Xerxes and Ariodante and Donizetti’s Maria Stuarda for English National Opera, and for the Royal Opera House, Covent Garden, her roles have included Cherubino, Dorabella, Donna Elvira, Rosina, Octavian, and new productions of L'enfant et les sortilèges, Ariadne auf Naxos, Idomeneo, Mitridate, Re di Ponto, Cosi fan tutte, Mosé in Egitto, Alcina and Giulio Cesare.

Much sought after as a concert singer, she has sung with the Orchestre de Paris under Kubelik, the Philadelphia Orchestra under Sawallisch, the Berlin Philharmonic Orchestra under Muti, the Chicago Symphony Orchestra under Solti, the Royal Concertgebouw Orchestra under Haitink and in the Musikverein, Vienna under Sawallisch and Harnoncourt. She sings in Great Britain with the leading orchestras, at the BBC Promenade Concerts (where she has sung at both the First and Last Nights of the Proms) and at the major festivals.

Ann’s recital appearances have taken her to Paris, Brussels, Amsterdam, Geneva, Dresden, Zurich, Frankfurt, Madrid, London, Dublin, the Aldeburgh, Edinburgh, Munich and Salzburg Festivals and both the Konzerthaus and Musikverein in Vienna. Her discography reflects not only her broad concert and recital repertoire but also many of her great operatic roles, including Purcell's Dido under Harnoncourt, Dorabella under Levine, Cherubino under Muti, Hansel under Colin Davis, Sextus under Harnoncourt and Donna Elvira under Solti.

Her operatic engagements have taken her to Hamburg, Dresden, Brussels, Paris, Berlin, Cologne, Zurich, Amsterdam, the Chicago Lyric Opera and the Metropolitan Opera, New York. At La Scala, Milan her roles have included Donna Elvira, Sextus, Dorabella and Cherubino under Muti. For the Bavarian State Opera, Munich she has sung Cherubino, Dorabella, Sextus, Elvira, the Composer, Octavian, Xerxes, Ariodante, Giulio Cesare and Rinaldo; at the Vienna State Opera Idamantes, Cherubino, Charlotte, Rosina, Octavian and the Composer; and at the Salzburg Festival Cecilio and Sextus under Cambreling, La Cenerentola under Chailly, Nicklausse and Cherubino under Levine, Dorabella and Donna Elvira under Muti and Octavian under Maazel.

Her recent engagements include Mrs Grose (The Turn of the Screw) at English National Opera, Countess (Pique Dame) at Welsh National Opera, Marcellina (Le nozze di Figaro), The Witch (Hansel und Gretel) and La Marquise de Berkenfeld (La Fille du Regiment) at the Royal Opera House. Her future engagements include Marcellina at the Paris Opera and at the Royal Opera House, Mrs Grose at the Theater an der Wien and for Los Angeles Opera, La Marquise de Berkenfeld at the Metropolitan Opera and at the Royal Opera House.

In 1997 the National University of Ireland made Ann an Honorary Doctor of Music. In 1998 she was made a Kammersängerin of the Bavarian State Opera and in 1999 an Honorary Fellow of the Royal Academy of Music. In the 2002 Golden Jubilee Queen’s Birthday Honours she was appointed an honorary Dame Commander of the Most Excellent Order of the British Empire. In 2004 she was awarded the Bavarian Order of Merit.