Born in Montreal in 1975, Nézet-Séguin early situated himself as a musical generalist, a trend he would sustain throughout his career studying piano, chamber music, choral and orchestral conducting, and composition at the Conservatoire de Musique du Québec and at Westminster Choir College. He had a lifelong admiration for the work of Carlo Maria Giulini and worked extensively with the Italian conductor during his final year of public performances.
When he was 14, Nézet-Séguin began leading rehearsals of the Chorale Polyphonique at the Montréal Cathedral, and he became the group's conductor at 19. The following year he founded Le Chapelle de Montréal, a vocal and instrumental group that began with a focus on the Baroque, but which Nézet-Séguin hopes will eventually perform a broad variety of music. In 1998, he became the chorus master and assistant music director of L'Opéra de Montréal. He was appointed artistic director and principal conductor of Orchestre Métropolitain du Grand Montréal in 2000. With the orchestra, he has recorded the works of a variety of composers, including Mahler, Bruckner, Debussy, Britten, Saint-Saëns, and Weill. In 2012, he became music director of the Philadelphia Orchestra as well. He is also active as a pianist and is featured on a number of discs as soloist and accompanist. In 2016, he was named as music director of the Metropolitan Opera, to start in the 2020-21 season.