Her operatic debut, as Pamina, was in Bob Wilson's "Magic Flute" at the Paris Opera under Jiri Kout. This was followed by more engagements as Pamina in Madrid and Paris under Marc Minkowski, as Papagena in Reggio Emilia, Ferrara, and Modena under Claudio Abbado, Xenia in "Boris Godunov" under Semyon Bychkov in Florence, and her debut with the Opernhaus Zürich as Guinia in Johann Christian Bach's "Lucio Silla" under Theodor Guschelbaur.
A return to Zürich as Serpetta in Mozart's "La Finta Giardinera" under Nikolaus Harnoncourt was the catalyst to an important collaborative relationship with Mo. Harnoncourt resulting in many projects to follow; Pamina in Zürich, Ilia in Mozart's "Idomeneo" in Graz and Zürich, as well as numerous concerts including her first Mozart's "c- minor Mass".
2006 saw Ms. Kleiter debuting as Susanna in "Le Nozze di Figaro" in Verona and Reggio Emilia and her debut as Celia in Moazart's "Lucio Silla" with director Jürgen Flimm in the hallowed ground of Venice's "Teatro la Fenice" followed by the Salzburg Festival.
Later that summer, she was heard in Mozart's "Betulia Liberata" as Amital and also Mozart's "Vesperae de Solennes de Confessore" under Riccardo Muti in Salzburg.
She concluded her summer season with performances of Mozart's "Magic Flute" (Pamina) under Claudio Abbado at the Edinburgh Festival.