He is one of the more absorbing and thoughtful practitioners within that idiom, and he is receptive to the idea of using material from the rock era (Paul McCartney's "Blackbird," for example). Though Mehldau's training is primarily classical, his interest in jazz began early. He played in the Hall High School jazz band in Hartford, Connecticut, winning the Berklee College of Music's Best All-Around Musician Award while still in his junior year of high school. He studied jazz at New York's New School for Social Research under Fred Hersch, Junior Mance, Kenny Werner, and Jimmy Cobb. Cobb soon hired him to play in his band, Cobb's Mob, and Mehldau also played and recorded with the Joshua Redman Quartet before forming his own trio in 1994 and recording his first Warner Bros. album, Introducing Brad Mehldau, in 1995. Art of the Trio, Vol. 1 followed in 1997, with the next two volumes in the series appearing over the following months. Two years later, Mehldau returned with Elegiac Cycle, as well as Art of the Trio, Vol. 4: Back at the Vanguard. Places followed in 2000, consisting of all-original compositions focusing on various cities, hence the title of the album.

Another Art of the Trio album came out in 2001, but the most significant release was Largo, which recorded Mehldau performing with other groups outside of his usual trio format. This was a big change from his previous work, and offered new challenges as he adapted to several interesting lineup situations. Mehldau followed the genre-bending album with the standards-based Anything Goes and Live in Tokyo in 2004, with Day Is Done arriving the following year. In 2006, he released House on Hill as well as Love Sublime, the latter with soprano vocalist Renée Fleming on Nonesuch Records. Mehldau chose to work with his trio plus Pat Metheny on Quartet in 2007; he followed it up with the double-disc Live in 2008, which was recorded with his trio at the Village Vanguard.

In 2010, Mehldau emerged with the ambitious Highway Rider, a double-disc of 15 new compositions produced by Jon Brion. He employed his trio as well as drummer Matt Chamberlain, saxophonist Joshua Redman, and a small chamber orchestra led by Dan Coleman. Mehldau arranged and orchestrated all the music. Also in 2010, Mehldau was honored by Carnegie Hall when he was named the first jazz artist to hold the Richard and Barbara Debs Composer's Chair for the 2010-2011 season. In 2011, Mehldau appeared on two live albums, his own Live in Marciac and the ECM date Live at Birdland (recorded in 2009) with saxophonist Lee Konitz, bassist Charlie Haden, and drummer Paul Motian. In September of that year, Nonesuch also released a studio album, Modern Music, a collaboration between Mehldau, pianist Kevin Hays, and composer/arranger Patrick Zimmerli. The music on this set comprised tunes by each of the principals, as well as compositions by Ornette Coleman, Steve Reich, and Philip Glass.

On December 6, 2011, while Mehldau was at the beginning of a world tour, Nonesuch issued a box set entitled Art of the Trio Recordings: 1996–2001. The set includes the five Art of the Trio albums -- the last a double disc -- that were originally issued on Warner Bros. The box also included a seventh disc of previously unreleased material from shows at the Village Vanguard in 1997, 1999, and 2001. A year later, the Brad Mehldau Trio released two studio albums with the all-original Ode and a companion collection of cover songs, Where Do You Start. The pianist then joined drummer/electronicist Mark Guiliana for the duo's collaborative 2014 effort, Mehliana: Taming the Dragon.

The box set 10 Years Solo Live appeared in 2015 and featured solo performances Mehldau had given in Europe in the preceding decade. He then returned to his tried-and-tested trio of Larry Grenadier and Jeff Ballard for 2016's Blues and Ballads, an album that featured their meticulous collective touch on compositions by Cole Porter, Charlie Parker, Lennon/McCartney, and others. Also in 2016, the pianist joined longtime associate saxophonist Joshua Redman for the duo album Nearness. ~ Richard S. Ginell & Thom Jurek