Prefer his half-half brother, Julian Lennon, Sean has pursued a career inside music. His initial efforts were collaborations. He appeared in Lenny Kravitz's 1991 album Mama Said, formed backing-band IMA for his mother's 1995 album Rising, and has collaborated by having a Up to date York-depending Japanese duo Cibo Matto.

Across his association by having Cibo Matto, he was approached per Beastie Boys' Adam Yauch, who expressed an interest around Sean's music. His debut solo album, Into the Sun, was released inside 1998 on the Beastie Boys's record label, Grand Royal Records. It garnered caring reviews. On Grand Royal, Sean has said, "I think I found the only label on the planet who doesn't care who my parents are and what my name is. It's a good feeling to know that I wouldn't have gotten the offer if they wouldn't have liked my songs. That's pretty rare in the music business!"

Inside 1999, Half Horse, Half Musician was released, the Japanese-sole compilation of outtakes & remixes from either Into A Sun. He besides manufactured the guest appearance on the underground hip-hop collaboration, Deltron 3030, working with genre legends Del Tha Funkee Homosapien and Dan Nakamura. Oddly plenty, Sean's role in a song seems to be describing the naturalistic Hell that Globe has become, antithetic to his father's song, "Imagine". His lyrics in the song come so:

"Looking up the sky is red, cities burning overhead. We can make the best of it, in this post-apocalypse."

Retiring girlfriends include Yuka Honda of Cibo Matto, Bijou Phillips, and Elizabeth Jagger, daughter of Mick Jagger.

When Grand Royal Records' demise within 2001, Sean signed with Capitol Records.