Eminem and Dr. Dre are easily one of hip-hop's most respected and consistent duos, having been amassing an incredible discography for a steady twenty-one years now. Even to this day, the longtime duo has continued to keep the creativity flowing, with Em's Music To Be Murdered By Side A & B featuring a slew of Dr. Dre productions -- many of which standout as album highlights.

Dr. Dre Eminem

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You'd be hard-pressed to find a hip-hop head who doesn't respect what Shady and Dre have brought to the table, and both parties have made their admiration for one another well-known throughout their time as collaborators. In fact, Eminem has long credited the Doc for "saving his life," gratitude explored with emotional depth on the 2011 single "I Need A Doctor." It's no surprise that on Dre's fifty-sixth birthday, a milestone celebrated by many of the rappers impacted by The Doc's brilliance behind the boards, Em took to Instagram to share some kind words to his mentor. 

"U know it’s Dre Day!" captions Slim, alongside a vintage picture from the MTV Music Awards in 1999, right around the time they first came together for The Slim Shady LP's "My Name Is," "Guilty Conscience," and "Role Models." "Happy bday Doc. I ain’t gotta say more you know what it is!" Indeed -- now, all we can hope for is a few notable inclusions from Eminem on whatever album Dre has been cooking up in the studio these days. After all, it was recently revealed that Em had to "trade" one of his own songs to score "Guns Blazing" for Side Bwhich all but guarantees another duet is on the way. 

Once again, happy birthday Dre!