Marty O'Brien is an American bass guitarist originally from Pawtucket, Rhode Island and currently based in Los Angeles. O'Brien plays professionally for live touring musical acts, recording sessions, television, and film scores all of which encompass a range of genres such as pop and rock, thereby collaborating with various musical artists. O'Brien's discography is generally diverse yet also maintains a notable background and standing in the hard rock and metal music genres. Live credits include tours with bands such as Disturbed, Tommy Lee, Static-X, Methods of Mayhem, Lita Ford, and many others. He has performed on three different Ozzfest tours, each time with a different band (Ozzfest's 1998, 2000, 2002). Also a busy session-bassist, most of this work taking place in his current home base of Los Angeles, O'Brien has recorded with numerous artists such as Celine Dion, Chris Cornell, Brian McKnight, Tommy Lee, Lindsay Lohan, Gus G., Lita Ford and Kelly Clarkson; the later includes the number one single, Because of You from the Grammy award-winning album titled Breakaway.