Being Earnest, and The Solid Gold Cadillac, as well as a number of less successful vehicles. She was nominated for the Laurence Olivier Award for Best Actress in a Supporting Role for her work in And a Nightingale Sang in 1979. A classically trained singer, she has occasionally made forays into operetta including taking the title role in an acclaimed production of Jacques Offenbach's La Grande-Duchesse de Gérolstein at the 1978 Camden Festival; "As the Grand Duchess she invested every phrase, spoken or sung [...] with wit and meaning, and coloured her tone to express a wide variety of emotions. Never did she resort to the hoydenish behaviour that this role – in British productions at least – seems to invite." Routledge made her Broadway debut in Roger Milner's comedy How's the World Treating You? in 1966, returning in the short-lived 1968 musical Darling of the Day, for which she won the Tony Award for Best Actress in a Musical, sharing the honour with Leslie Uggams of Hallelujah, Baby! Following this, Routledge had roles in several more unsuccessful Broadway productions including a musical called Love Match, in which she played Queen Victoria; the legendary 1976 Leonard Bernstein flop 1600 Pennsylvania Avenue, in which she portrayed every U.S. First Lady from Abigail Adams to Eleanor Roosevelt; and a 1981 musical, Say Hello to Harvey – based on the Mary Coyle Chase play Harvey (1944) – which closed in Toronto before reaching New York City. In 1980, Routledge played Ruth in the Joseph Papp production of The Pirates of Penzance, co-starring American actor Kevin Kline and pop vocalist Linda Ronstadt, at the Delacorte Theatre in New York City's Central Park, one of a series of Shakespeare in the Park summer events. The show was a hit and transferred to Broadway the following January, with Estelle Parsons replacing Routledge. A DVD of the Central Park production, with Routledge, was released in October 2002. She also performed in Façade at New York's Carnegie Recital Hall. Routledge won a Laurence Olivier Award in 1988 for her portrayal of the Old Lady in Leonard Bernstein's Candide in the London cast of the critically acclaimed Scottish Opera production. One critic noted "She stopped the show with 'I am so easily assimilated', and her long narration worked on at least two levels – it was both hilarious and oddly moving." She also played the role of Nettie Fowler