Gang Starr was originally a trio formed by rapper Keith "Guru" Elam in Boston. Guru relocated to Brooklyn and teamed up with producer Chris "DJ Premier" Martin (originally from Texas). This two-men Gang Starr debuted with the single Words I Manifest (1989) that sampled Dizzy Gillespie's Night in Tunisia (1952). They were among the earliest hip-hop musicians to follow Public Enemy's lead into social commentary, but, most importantly, their No More Mr Nice Guy (1989), containing the manifesto Jazz Music and Manifest, was one of the first experiments at mixing jazz and rap. Their song Jazz Thing for the soundtrack of Spike Lee's film Mo' Better Blues (1990) made jazz-hop even more popular.

Step In The Arena (1990), their masterpiece (Just to Get a Rep, Love Sick, Step in the Arena, Execution of a Chump), refined that approach, and Daily Operation (1992), with Take It Personal, Soliloquy of Chaos and Ex Girl To The Next Girl, was no less inventive while being more accessible.

Hard to Earn (1994), with Code of the Streets and the proud self-tribute of Mass Appeal, recycled the same praxis without any new element.

Moment of Truth (1998), with You Know My Streez, Moment of Truth and Above The Clouds, was instead an ambitious attempt at completely redefining their aesthetics.

Full Clip (1999) is a double-disc retrospective.

Martin's extensive use of jazz sampling and percussion loops revolutionized the way "raps" ought to be orchestrated.

After Gang Starr split, Keith "Guru" Elam released one of the milestones of jazz-hop fusion, Jazzmatazz Volume 1 (1993), where he used guest jazz musicians as samples of jazz music, but with a humane voice (Transit Ride, Trust Me, Loungin', Sights in the City). In fact, Guru laid the mechanical beats first, and then let the jazz musicians play on top of it, thus de-facto restraining the degree of their improvisations. It was the first of a series of star-studded solo albums: The New Reality (1995), Streetsoul (2000).

Between 1993 and 2007, Guru also released four solo albums titled Jazzmatazz. He died of a heart attack in 2010.