Lee Doo-hyun ( Hangul: 이두현; born 1980), better known by his stage name Ra.D ( Hangul: 라디) is a South Korean singer-songwriter and producer who debuted in 2002 with the album My Name is Ra.D. After establishing his own record label, RealCollabo, he has been participating in the production of many artists' albums since. After a 6-year hiatus, he made a comeback in February 2013 with the single "It's Been a While".
Ra.D has produced for artists such as 2PM, Brown Eyed Girls' Gain, Dynamic Duo, KeBee, UMC, Ahn Trio and Cho PD.
On October 26, 2015, he announced RealCollabo would be closed after established for seven years. "Draw You", a collaboration project of Ra.D, d.ear, Brother Su, and Jooyoung, is the last release from this label (co-release with 24thStreet).