Nagano's interest in and championing of contemporary music is exemplified in his relationships with both Olivier Messiaen and John Adams.

Nagano gave the United States première of Messiaen's La Transfiguration de notre Seigneur Jésus Christ with the Berkeley Symphony Orchestra for which Messiaen travelled to California.  That led to Nagano's participation in the world première of Messiaen's Saint François d'Assise as assistant to Seiji Ozawa at the Opéra de Paris in 1983.  At the beginning of the 2002/03 season - a decade after Messiaen's death - Nagano conducted the Deutsches Symphonie Orchester Berlin in performances of both La Transfiguration de notre Seigneur Jésus Christ and his last work, Eclairs sur l'Au-dela, which the orchestra had given the German première of, under their previous Chief Conductor, Vladimir Ashkenazy.

John Adams also has a long history with Kent Nagano; the controversial opera The Death of Klinghoffer was given its première by Nagano and his Opéra de Lyon forces in 1992, and Nagano has returned to the work to conduct a television version.  While he was at the Hallé, Nagano premièred Slonimsky's Earbox, which was a Hallé co-commission in 1996 to celebrate the orchestra's move to Bridgewater Hall and also recorded El Dorado (1991).  In 1998 Nagano gave the first London performance of Nixon in China, with the London Symphony, in concert, and he conducted the world première of El Niño at the Paris Théatre du Chatelet, which won the 2002 Gramophone Best DVD Award.