While studying classical singing and chamber music at the Conservatory of Liege, Marianne Pousseur has sung in both ensembles directed by Philippe Herreweghe, Collegium Vocale and La Chapelle Royale.
She participates simultaneously in several performances of the Théâtre du Ciel Noir directed by Isabelle Pousseur. The stage version of Pierrot Lunaire by Arnold Schoenberg has been a film with Ensemble Musique Oblique conducted by Philippe Herreweghe, and a CD recording for the label Harmonia Mundi France.
She performs regularly with ensembles such as the Schoenberg Ensemble in The Hague, (direction Reinbert de Leeuw), Remix Porto, Die Reihe Vienna, etc.. and with the Ensemble Intercontemporain, particularly under the direction of Pierre Boulez, in a repertoire essentially turned the twentieth century, the creation and musical theater. She was invited by the Festival d'Automne in Paris to interpret Infinito Nero by Salvatore Sciarrino, she is also an actress in Lohengrin with Ensemble Intercontemporain, with ASKO (Amsterdam), with Ensemble Risognanze (Milano). With this latest ensemble she records “Lohengrin” for the label "Col Legno", published in 2008. This recording won the 2009 MIDEM Classical Awards in Cannes.
His theatrical experience allows her to be actress reciting in symphonic works as Psyche by César Franck and "Peer Gynt" by Grieg in a concert version conducted by Kurt Masur with the Orchestra National de France and the London Philharmonic Orchestra .
In collaboration with Enrico Bagnoli, she staged several musical theater creations include: "Songbooks" and John Cage's "Song of darkness", a show built from songs by Hanns Eisler and Bertolt Brecht. "Babar" by Poulenc, with Leonardo da Vinci Orchestra conducted by Oswald Sallaberger. With the same collaborators, she also designs a staging of "L’enfant et les sortilèges" by Maurice Ravel. Ismene (2008) and Phèdre (2013)
For her, George Aperghis composed in 2004 "Dark Side", created in Athens with the Ensemble Intercontemporain. After this, they decide to work together again on "Ismene" poem by Yannis Ritsos, transformed into an opera for solo voice and created in autumn 2008. this performance won in 2009 the Belgian critics Award and it is performed in several international festivals as Musica in Strasbourg, GMEM in Marseille, Vie in Modena and Festival d’Automne in Paris.