Lee Ji-hoon (Korean: 이지훈), born November 22, 1996 in Gwangan-dong, Busan, South Korea, is a South Korean singer-songwriter and producer. Better known by his stage name Woozi (Korean: 우지), he is a member of the K-pop boy group SEVENTEEN and the leader of its vocal team sub-unit. Woozi plays a large role in the production of SEVENTEEN's music. He has been a full member of the Korea Music Copyright Association (KOMCA) since 2019. Woozi studied classical music and played the clarinet as a child, and now plays several other instruments, including the piano, guitar, and drums. He joined Pledis Entertainment through auditions, where he became part of the groups of trainees who would eventually form SEVENTEEN. During this time, he met his mentor Bumzu, with whom he still collaborates to this day. As a trainee, Woozi appeared in music videos for label-mates NU'EST, Hello Venus and Orange Caramel. Outside of SEVENTEEN, he has composed songs for I.O.I, BAEKHO, and fromis_9, among others. He appeared in the pre-debut online program SEVENTEEN TV alongside other SEVENTEEN members, and continues to participate in the group's ongoing web-series GOING SEVENTEEN.