Thaddis "Kuk" Harrell is an American songwriter, vocal producer, arranger and engineer. He is managed by RedZone Entertainment, and is a member of a songwriting–production team composed of himself, Christopher "Tricky" Stewart and Terius "The Dream" Nash. In 2011, Kuk Harrell and partner Tricky Stewart joined the ranks of Fox's American Idol along with music mogul Jimmy Iovine, producing many of the songs performed on television by the contestants and released via iTunes. 2011 marked the highly-anticipated return of Jennifer Lopez and her album LOVE? in which Kuk served as Album Vocal Producer. Earning his fourth Grammy for the vocal production of Rihanna's #1 Billboard Single "Only Girl In The World", Harrell is also the vocal producer and co-writer of Rihanna's Grammy-winning single "Umbrella". A composer and engineer on Beyoncé's chart topping "Single Ladies (Put A Ring On It)" from the album I Am... Sasha Fierce, he is also vocal producer and engineer of the Diane Warren-penned "I Was Here" from Beyoncé's 2011 album 4. He also produced the majority of the vocals on Mary J. Blige's Platinum album Growing Pains, which recently won a Grammy for "Best Contemporary R&B Album", 2008. The first single from Growing Pains, "Just Fine", earned a Grammy nomination for best R&B vocal performance in 2007.

Kuk Harrell is currently signed to a worldwide publishing deal with Sony/ATV U.K., and is considered one of the most sought after vocal producers in the industry.