Guru (born Keith Edward Elam in Boston) and Premier (born Christopher Edward Martin in Houston) began working together in 1989. Guru founded Gang Starr a couple years earlier and had already established a working relationship with Wild Pitch Records. The partnership of Guru and Premier as Gang Starr led to a formative debut album, No More Mr. Nice Guy (1989), including the featured single "Words I Manifest" and the DJ-spotlight track "DJ Premier in Deep Concentration." Between albums, in 1990, Guru and Premier contributed "Jazz Thing" to the Mo' Better Blues soundtrack. Gang Starr subsequently moved to Chrysalis Records for their second album, Step in the Arena (1991), on which they perfected the approach of their debut — a stark, hard-hitting jazz-rap production style, complete with Premier's masterful DJ cutting, over which Guru's battle-rap-hardened yet smoothly delivered lyrics, often thoughtful, sly, and streetsmart, take flight. Gang Starr's third album, Daily Operation (1992), furthered the duo's approach stylistically; widely considered an East Coast rap classic, it's arguably Guru and Premier's finest work, along with its predecessor.
In 1998, after four years between albums, Gang Starr returned with Moment of Truth, their first album to chart at number one (on the R&B/Hip-Hop album chart, that is; it peaked at number six on the Billboard 200 overall, their best showing). Moment of Truth was a significant departure from past Gang Starr efforts, very much contemporary in style; for example, the album features numerous guests (Inspectah Deck, Scarface, G. Dep, K-Ci & JoJo, M.O.P.) and bore little trace of the duo's jazz-rap beginnings. The lead single, "You Know My Steez," became the second Gang Starr hit to break into the Hot 100 (peaking at number 76). A double-disc retrospective, Full Clip: A Decade of Gang Starr (1999), subsequently marked the duo's ten-year anniversary. In the years that followed, Guru and Premier continued to focus on their own work. Guru continued his Jazzmatazz series, beginning with a third volume, Streetsoul (2000); he also released solo rap albums, beginning with Baldhead Slick & da Click (2001). The next Guru release, Version 7.0: The Street Scriptures (2005), arrived on his new label, 7 Grand Records; the album featured beats by Solar, who would prove to be an important contributor on additional 7 Grand releases. The fourth volume of Jazzmatazz (2007) included the typical array of guest vocalists and instrumentalists and was issued along with the "raw" companion disc Guru's Jazzmatazz - The Timebomb: Back to the Future Mixtape. Guru 8.0: Lost and Found (2009), the rapper's next 7 Grand full-length, followed shortly thereafter. Premier continued his production activity, working with superstars such as Jay-Z, Nas, and Common, as well as underground rappers such as Royce da 5'9", Termanology, and NYG'z; he even dabbled in mainstream pop, most notably working extensively with Christina Aguilera on her double-disc album Back to Basics (2006), including the Top Ten hit "Ain't No Other Man."