Richard Martin Lloyd Walters (born January 14, 1965), better known as Slick Rick, is an English-American rapper and record producer. He rose to prominence as part of Doug E. Fresh & the Get Fresh Crew in the mid-1980s. Their songs "The Show" and "La Di Da Di" are considered early hip hop classics. "La Di Da Di" is one of the most sampled songs in history.

In 1986, Slick Rick became the third artist to sign with Def Jam Recordings. He has released four albums with the label: The Great Adventures of Slick Rick (1988), The Ruler's Back (1991), Behind Bars (1994) and The Art of Storytelling (1999). His music has been sampled and interpolated over 1,000 times, in songs by artists including Eminem, Beyoncé, Mariah Carey, Beastie Boys, TLC, Nas, Miley Cyrus, Kanye West, MF Doom, Czarface, Black Star, The Notorious B.I.G., Snoop Dogg, MC Ren, Montell Jordan, Tech N9ne and Color Me Badd. In the process, Slick Rick has become one of the most-sampled hip-hop artists of all time. Many of these songs based on Slick Rick samples went on to become hit singles. He was one of the first hip-hop artists to be covered, when Snoop Dogg (then Snoop Doggy Dogg) rapped Rick's lyrics from his record "La Di Da Di" almost in their entirety on the track "Lodi Dodi" on his debut album Doggystyle in 1993. At the time, it was uncommon for rappers to record covers of each other's material.

Slick Rick has been a VH1 Hip Hop Honors honoree, and About.com ranked him No. 12 on their list of the Top 50 MCs of Our Time, while The Source ranked him No. 15 on their list of the Top 50 Lyricists of All Time.