In November, 1961, she made her Metropolitan Opera debut in New York as Fiordiligi, remaining on its roster for the season. She returned for the 1966-70 and 1972-73 seasons. Her tours as a soloist with orchestras and as a recitalist took her all over the globe until her retirement in 1984. Curtin taught at the Aspen (CO) School of Music and the Berkshire Music Center in Tanglewood. After serving as professor of voice at the Yale University School of Music (1974-83), she was professor of voice and dean of the school of arts at Boston University (from 1983). In 1992, she retired as its dean but continued to teach there. Curtin became well known for such roles as Mozart’s Countess, Donna Anna, Rosalinde, Eva, Violetta, Alice Ford, Salome and Ellen Orford. She also created Floyd’s Susannah (1955) and Cathy in “Wuthering Heights” (1958).
She taught in the Beijing Conservatory, the Moscow Conservatory and in Tbilisi. She taught a Master Class at the Tanglewood Music Center, summer home of the Boston Symphony. She also taught at the Music School in Boston University’s College of Fine Arts where she served as Dean Emerita of the College and artistic adviser to the Opera Institute.