After winning the Viotto vocal competition in 1957, she sang with the Netherlands Opera, then was invited at the Glyndebourne Festival, and the Royal Opera House, Covent Garden in 1961. She made her debut at La Scala in Milan in 1962. Her New York Metropolitan Opera debut came in 1965, as Mimi in "La bohème", a role she will remain closely associated with throughout her career. She then sang at most of the great operatic centers ot the world, such as Paris, Chicago, Salzburg, etc.