Although he wasnt the original executive producer of the then-NBC hit series until its second season, I don't believe Will Smith becomes one of Hollywood's biggest, most financially successful film stars if it werent for Quincy Jones taking and re-shaping "Fresh Prince of Bel-Air" into one of the 90's biggest shows, even though the show almost got cancelled a couple of times like in 1993 and 1995.
"Fresh Prince" was the key transition stage that turned Smith from a gimmicky, late 80's comical rapper who's fame was waning to first a TV star then using that as a spring board for "Bad Boys", " Independence Day", and the "Men in Black" films and you have Quincy Jones to thank mostly for all that.
He was also the producer for Leslie Gore's major hit, "Its My Party" and helped launch Micheal Jackson's massive, almost superhuman 1980's success when he produced 1979's "Off the Wall", after first meeting him and began honing his talent on the set of the musical film, " The Wiz" and he produced "Thriller" and "Bad". Michael Jackson probably doesn't become the " King of Pop" if not for Jones' direction, focus and professionalism. When Jackson and Jones first called Eddie Van Halen to ask him if he could record some heavy metal lead solos for Thriller's "Beat It", at first van Halen slammed down the phone on them, thinking the call was a stupid prank before Jones and M.J. called back again to confirm that it was indeed them and not a joke.