Born in La Rochelle, Saunier began learning the trumpet at the School of Municipal Music in Surgères with Christian Méchin.
Saunier has been the principal trumpet of Pierre Boulez' Ensemble Intercontemporain since 2013 and collaborates with the great composers and conductors of our time such as Matthias Pintscher, Péter Eötvös, Simon Rattle, Pablo Heras-Casado, Yan Maresz, Martín Matalon, Pascal Dusapin...
In 1998, he founded the Academy of Brass and Percussions of Surgères, which he coordinates and which now welcomes 150 participants each summer under the supervision of an international teaching team.
Between 2007 and 2009, he recorded a solo album with prestigious ensembles throughout Europe, including the English Chamber Orchestra and the Amici Musicae[5] in Leipzig.
The record Directions (2017) includes modern pieces for trumpet alone by Henze, Takemitsu, Scelsi, Fedele, Peter Maxwell Davies, Pintscher.