Ballard starred on Broadway as Helen in The Golden Apple, introducing the song "Lazy Afternoon". She portrayed Rosalie in Carnival!, Ruth in Joseph Papp's The Pirates of Penzance, and the title role in Molly, an unsuccessful musical adaptation of the popular radio serial The Goldbergs. She created the role of the Countess and closed out-of-town in Marc Blitzstein's Reuben, Reuben, and played Ruth Sherwood in Wonderful Town at New York City Center in 1963.