The duo of Talib Kweli and Hi-Tek met in Tek's native Cincinnati, Ohio, following the release of the Hi-Tek/Mood collaboration "Hustle on the Side". Kweli and Hi-Tek made their first official collaboration in 1997 on Mood's debut album, Doom, on the track "Industry Lies". That same year, the two formed as Reflection Eternal, and signed to upstart underground hip hop label Rawkus Records. The tracks from their debut single, "Fortified Live" b/w "2000 Seasons", were included on the Rawkus Records compilation Soundbombing in October 1997. In 1998, Kweli and his high school friend, fellow Rawkus Records artist Mos Def, formed the duo Black Star, and released their first, and only album, Black Star, to rave reviews. Hi-Tek provided production for a number of songs on the album, including the singles "Definition" and "Respiration". The album put the three at the forefront of an underground hip hop scene that appeared at the time to be flagging against the influence of the "Jiggy" era of hip-hop, and was followed by a number of acclaimed collaborations and albums. Kweli and Hi-Tek reconnected in 2000 for the release of their debut album, Train of Thought. Though highly acclaimed, the release did not receive a significant amount of commercial attention, despite the success of the rap hits "Move Somethin'" and "The Blast".
Following the Train of Thought album, the duo split for solo projects, beginning with Hi-Tek's Hi-Teknology, released in 2001, on which Kweli appeared. The album didn't receive as much attention or as many sales as Train of Thought, though the single "Round & Round" became a crossover hit in 2002. Kweli released his first solo album, Quality, in late 2002. In a 2002 interview he also stated that another Reflection Eternal and Black Star album would be released. Hi-Tek was not involved with the project's production, instead featuring beats from artists like Kanye West, DJ Scratch, DJ Quik, Ayatollah and J Dilla. The Kanye West-produced single "Get By" became Kweli's biggest success, charting on the Billboard Hot 100 in 2003. Kweli's second solo album, 2004's The Beautiful Struggle, saw the duo working together once again, with three tracks produced by Hi-Tek. Kweli released his next album, Ear Drum, in 2007, featuring production from Tek; Hi-Tek released the follow-up to his debut, Hi-Teknology 2: The Chip, in 2006 and his third album, Hi-Teknology 3: The Underground, in 2007, both on Babygrande Records and both featuring appearances by Kweli.
The duo announced that another Reflection Eternal album was in the works in 2008. They named their second album Revolutions Per Minute. They played a live reunion gig in Toronto, Ontario, Canada on September 20, 2009. In the same year Bootsy Collins collaborated with Talib Kweli and Hi-Tek on the track "Internet Connection". also a track "Back Again" has been released along with video. They also collaborated with J. Cole, Mos Def, and Jay Electronica on the track "Just Begun". These 3 songs were released in a mixtape on January 1, 2010 called The Re:Union which received positive fanbase feedback. Their second album Revolutions Per Minute was released on May 18, 2010 with similar praise as their debut album. It spawned 3 singles: "In This World", "Strangers (Paranoid)" featuring former UGK member Bun B, and Midnight Hour featuring Atlantic recording artist Estelle.