Gregory Lyle Gisbert was born in Mobile, Alabama, on February 2, 1966, to two music teachers, and the household put an instrument in his hands early: he played drums in his father's trio at hospitals, lodges and VFW halls before he was old enough to read a chart. The family moved to Colorado in 1971, when he was five, and Denver rather than Alabama is where the musician was made. At Walt Whitman Elementary his drumming carried across the school grounds at recess, which he sometimes skipped in order to practise in the hall. He was pushed toward cornet on the practical grounds that his arms were long enough for it, and he resisted the switch until he saw Clark Terry play live, after which he took up the trumpet in earnest. As a teenager he was a regular at El Chapultepec, the Denver club whose owner Jerry Krantz let him sit in with the house musicians Ken Walker and Ellyn Rucker. He played in the Colorado All-State Jazz Band in 1983 and was selected for the 1983/84 McDonald's All-American High School Jazz Band, touring with it and recording the Coast to Coast album while still at Heritage High School.

A scholarship took him to the Berklee College of Music for 1984 and 1985, where he played in Phil Wilson's Rainbow Band alongside the young Cyrus Chestnut and recorded the band's Latin American Tour. He did not stay to finish. Wilson put his name forward for the trumpet section of Buddy Rich's big band, and Gisbert made his debut with Rich on August 2, 1985, at nineteen, holding the chair into 1986. Woody Herman's orchestra under Frank Tiberi's direction followed from 1987 to 1989, and from there the calls came from the New York large-ensemble world he would spend the next three decades inside: Toshiko Akiyoshi from 1989 onward, Gary Burton and Lew Anderson in the same year, and John Fedchock and Maria Schneider as both were beginning to write for their own bands.

The 1990s were spent freelancing out of New York. He played in the Mingus Epitaph orchestra from 1990 to 1992, with Frank Wess, Clark Terry, Mickey Tucker and Buck Clayton in 1991, with Danny D'Imperio from the same year, and with Norman Simmons and John Hicks in 1992. The recordings from that stretch put him in fast company very quickly: Akiyoshi's Carnegie Hall Concert for Columbia in 1992, Tucker's Hang In There for SteepleChase in December 1991, and Hicks's Friends Old and New, cut at BMG's New York studio on January 14, 1992, where the front line paired him with Clark Terry and Al Grey over Ron Carter, Grady Tate and a very young Joshua Redman. In May 1994 he was one of eleven trumpeters on Burning for Buddy, the Rich tribute Neil Peart produced at the Power Station. He worked with the Joe Roccisano Orchestra from 1994 to 1997, recorded with Chuck Bergeron, Loren Schoenberg and Ken Peplowski, and backed Carol Sloane and Susannah McCorkle in large ensembles in 1996.

His own catalogue is small, concentrated and almost entirely on one label. Harcology was recorded at RPM Studio in New York on December 28, 1992, by a quintet of Chris Potter, John Campbell, Dwayne Burno and Gregory Hutchinson, and issued by Criss Cross Jazz. Big Lunage, co-led with the saxophonist John Gunther for Capri in 1994, was cut with the Denver rhythm section of Eric Gunnison, Mark Simon and Paul Romaine that would become his home band. On Second Thought (recorded December 11, 1994) added Steve Wilson on alto and put Peter Washington and Billy Drummond in the rhythm section, and The Court Jester (recorded December 27, 1996) is the largest of them, a septet with Jon Gordon, Tim Ries and Conrad Herwig playing his own "Robyn Song" and title track alongside Charlie Chaplin's "Smile" and "Dizzy Atmosphere". Criss Cross has released five albums carrying his name, the three leader dates plus Gary Smulyan's Blue Suite and Ries's Alternate Side.

The longest single association of his career is with the Maria Schneider Orchestra, whose trumpet section he has occupied since its first record. He plays on Evanescence (taped September 1992), Coming About (November 1995), Allégresse (January 2000), Days of Wine and Roses, cut live at the Jazz Standard in the same month, Concert in the Garden (March 2004), The Thompson Fields (August 2014) and Data Lords (August and September 2019), soloing on each; the last three all won Grammy Awards. The same band is why his horn is on a David Bowie record: Schneider arranged and conducted "Sue (Or In a Season of Crime)", released by Parlophone on November 14, 2014, and Gisbert plays trumpet and flugelhorn on the title track, which fills the A side and returns as a radio edit on the B side.

He has held or filled comparable chairs almost everywhere large-ensemble jazz is written in New York. He is on the Vanguard Jazz Orchestra's Up From the Skies, the 2006 album of Jim McNeely's writing, and had already recorded McNeely's Group Therapy with his tentet in June 2000. He played in the Jimmy Heath Big Band across both its records, Turn Up the Heath in 2004 and 2006 and Togetherness, taped live at the Blue Note on October 30 and 31, 2011, where he was one of five trumpets beside Roy Hargrove, Frank Greene, Diego Urcola and Michael Philip Mossman. He was in the Dizzy Gillespie All-Star Big Band under Slide Hampton's direction for Dizzy's Business and I'm BeBoppin' Too, in Hargrove's own big band for Emergence, in Ron Carter's Great Big Band, in the Ted Nash Big Band for the Grammy-winning Presidential Suite, in the Jazz at Lincoln Center Orchestra with Wynton Marsalis for Handful of Keys, and in Ryan Truesdell's Gil Evans Project for all three of its albums, taking solos on three tracks of the 2012 Centennial. He also took a trumpet chair in the Eyal Vilner Big Band for Almost Sunrise, recorded in Brooklyn in June 2014.

Colorado has always been the other half of the story. Convergence, the co-operative sextet he founded with Gunnison, Gunther, the trombonist Mark Patterson, Simon and Romaine, has made three albums for Capri across more than twenty years, from Hometown in 2002 to Reckless Meter, taped before an audience in Denver on April 7, 2019 and released in 2025. He produced and mixed the Japanese composer Chie Imaizumi's debut Unfailing Kindness, recorded in Wheat Ridge, Colorado, in February 2006, which is how her writing first reached a national audience. He founded the Greg Gisbert Syndicate in 2016 and played an eight-week residency with it at Denver's Nocturne Jazz and Supper Club, the band including the guitarist Steve Kovalcheck, the bassist Patrick McDevitt, the pianist Annie Booth and the drummer Mark Emmons. He has taught at the Juilliard School, the Manhattan School of Music, the Colorado Conservatory for the Jazz Arts and, over two stints in the 2000s, the University of Miami, and he is now a Lecturer in Jazz Studies at the University of Colorado Boulder, where he teaches jazz trumpet. On October 29, 2024 he was inducted into the Colorado Music Hall of Fame in its Mile High Jazz Oasis class, alongside El Chapultepec and Jerry Krantz, Eric Gunnison, KUVO and Carlos Lando, Ellyn Rucker and Ken Walker.

Gisbert names three models, and they explain most of what he does: Clark Terry, Thad Jones and Tom Harrell. From Terry come the wide range, the warmth at the bottom of the horn and the willingness to be funny; from Jones the sense that a solo inside a big band is an extension of the arrangement rather than an interruption of it; from Harrell the long, unhurried melodic line. AllMusic files him under bop, hard bop and post-bop, and its review of On Second Thought singles out his muted playing on Thad Jones's "Fingers" while noting drily that he "is not quite as well known as his sidemen" but keeps up with them throughout. Reviewing The Court Jester for All About Jazz in September 1999, C. Andrew Hovan heard "shades of Ellington and Strayhorn" in his muted work on "The Love Dirge" and called the trumpet shouts near the end of the title track "some of his finest recorded moments to date", while praising the way the septet voicings showed a composer maturing. What makes him valuable to bandleaders is a particular combination that is rarer than it sounds: a lead-strength upper register and a section player's discipline joined to a soloist worth featuring, which is why Schneider, McNeely, Truesdell, Nash and Heath all wrote him solos rather than simply parts. He is also a Denver player in a way that has shaped the music: reviewing Convergence's Reckless Meter for All About Jazz in January 2026, Pierre Giroux described a band built "through years of shared bandstands" rather than assembled for a session, which is a fair account of what Gisbert has spent three decades doing in two cities at once.