It was in 1978 when Boesch came to prominence, as Papageno in Die Zauberflöte, at the Salzburg Festival, in Jean-Pierre Ponnelle's production, conducted by James Levine.
He returned for the same opera in 1981 (now with Lucia Popp and Gail Robinson alternating as Pamina, and Zdzisława Donat as the Queen of Night), and the same season sang Monsieur Presto in the Met premiere of Les mamelles de Tirésias (directed by John Dexter).
In 1983, he appeared again at that theatre for their Centennial Gala and Don Giovanni (as Masetto), opposite James Morris, Edda Moser, Carol Neblett, Paul Plishka, Roberta Alexander and John Macurdy.
In Paris, in 1991, he resumed his most famous part, Papageno, in Robert Wilson's production of Die Zauberflöte, conducted by Armin Jordan.
The Kammersänger was also responsible for the concept and script of "Die Zauberflöte für Kinder," which introduced many youngsters to opera, and was published on DVD in 2007.