When Lorin Maazel was asked, during his first press conference as the Philharmonic's Music Director designate, for his view of contemporary music programming, he responded: "Conductors should perform music by composers they believe in." And he has done just that, shepherding, in past seasons, new and recent works by such composers as John Adams, Aaron Jay Kernis, Krzysztof Penderecki, and Rodion Shchedrin, and this season, commissioning new works by Augusta Read Thomas, Mark-Anthony Turnage, and Wolfgang Rihm. (A fourth commission, The Roaring Mountain, a piece for a Young People's Concert on April 2, will go to Jon Deak, the Philharmonic's Associate Principal Bass and a composer renowned for his fantasy and wit.)

This year's Philharmonic-commissioned composers are among the boldest modernist voices around, each in his or her own distinctive and alluring way. "We're keen to bring in to the loop talented composers from as many diverse compositional languages as possible," Mr. Maazel says, adding: "A commissioned work is always an adventure."

Perhaps it's his own experience as an accomplished composer that makes the Music Director's interest in new works so intense. Certainly Augusta Read Thomas, composer-in-residence with the Chicago Symphony Orchestra and the composer of the season's first commission, Gathering Paradise: Emily Dickinson Settings for Soprano and Orchestra, which premieres on September 29, found it so. "In the fall of 2002 Mr. Maazel was conducting the Chicago Symphony Orchestra. I was told that he had, of his own free will, asked for scores and CDs and taken them to his hotel room to study. A few months later, the Orchestra called my publisher to offer a commission. I will never forget the kindness he showed to my work." Thomas is an intellectually fastidious composer ‹ like her great Chicago predecessor, the architect Mies van der Rohe, she likes to think that "God is in the details." Her works avoid traditional tonality, but the whirling color, intensive lyricism, and expressive passion of her music give it a visceral appeal.

The music of Mark-Anthony Turnage, which the Philharmonic will showcase beginning on January 12 with the world premiere of Scherzoid (a co-commission with the London Philharmonic Orchestra), can also pack a punch, but its power comes from a different, more volatile mixture of source material, a combination of Stravinskyan modernism and jazz influences from such masters as the trumpeter Miles Davis and the guitarist John Scofield. (In Lorin Maazel's words, Mr. Turnage's dense music exploits orchestral resources "to the nth degree.") But Mr. Turnage has a strong classical urge as well; as James M. Keller noted in the program note for the Philharmonic's performance of the British composer's A Quick Blast last January, his music is "always zeroing in on a sound marked by rhythmic decisiveness and clarity."

"I originally planned Scherzoid as a scherzo that would be schizophrenic‹a piece that would constantly change its personality," Mr. Turnage says. "But after a run-through with the Philharmonic last March, I decided to make it less crazy and more clear. The title now refers as much to the process of writing the piece as it does to the piece itself." The work will be conducted by the Philharmonic's new Assistant Conductor, Xian Zhang, who will share the podium for these concerts with Mr. Maazel.

Wolfgang Rihm's music has a serenity and poise that is very different from Mr. Turnage's style, even though works like his concerto for chamber orchestra, Jagden und Formen, can teem with complex activity. As a composer who can enthuse about Rachmaninoff and Debussy as well as Stockhausen, Mr. Rihm is a centering influence on the European scene, an artist who considers and absorbs the work of a variety of creators through the prism of an intuitive working method. Mr. Maazel, who knows Mr. Rihm well from his years of living in Europe and who will conduct the world-premiere performances of the (still untitled) work beginning on March 10, accepts the challenge of his music with confidence: "I know just what to expect."

Russell Platt is a composer and an editor at The New Yorker.