Although she began singing and writing songs at age thirteen in Swansea, Wales, she decided to head into law and attended Sussex University. However, she spent less time and energy on studies and focused on being a DJ agent, although she did eventually receive a degree in law. There in Brighton, she spent a lot of time promoting club nights, and helped set-up and run the specialist breaks label Marine Parade. She has said she "went to class as little as [she] could without being kicked out".
In November 1999, she assembled a mobile studio where she further developed her songwriting and music production skills. During this period, she completed four demos that would eventually set up her career in the music industry. From there, she moved to London where she collaborated with Guy Sigsworth, and then to Brooklyn to work with Ge-Ology, (Mos Def, Talib Kweli). In autumn 2002 she met Yoad Nevo, who became her co-producer.
She was subsequently signed to the label ATO and released the moderately successful EP It All Starts Here in autumn 2003, followed by the album Finally Woken in March 2004.
Jem released the single "24" from Finally Woken on 2003 as a limited edition promo single, and then released her debut single, "They", from the same album, which followed the next year in her homeland of the UK, with a separate video. A remix of the song was the first release on her vinyl imprint label CrazyWiseMusic.
Further singles followed in the UK, before she took a gap to write and record a new album. Whilst working on the album, with Lester Mendez, she wrote a song called "Once In Every Lifetime" for the "Eragon" movie soundtrack. According to the press release, the new album will feature "a sprinkle of hip hop, a sprinkle of funk, a sprinkle of rock, an extra juicy helping of dance floor magic, and this time around some Cuban salsa and Japanese vibes mixed in for good measure." The song, "It's Amazing" from the "Sex and the City" movie soundtrack is the official first single from her second album, which she has entitled Down To Earth, released September 16th.
Her music has been featured on numerous television shows such as The O.C., Desperate Housewives, Wonderfalls, Six Feet Under, Crossing Jordan, Grey's Anatomy, and "Wish I" was used as the theme tune to the ITV show Celebrity Love Island.
Jem performed live at KCRW Radio in 2002 and 2004; WOXY in 2004; Popworld, Glastonbury, Coachella Valley Music and Arts Festival, Sasquatch! Music Festival, V Festival, and Top of the Pops in 2005.
| Song | Production | Year | Where |
|---|---|---|---|
| "Come on Closer" | "Closer" | 2004 | trailer |
| "Wish I" | "Celebrity Love Island" "Grey's Anatomy" S. 1, Ep. 7 | 2004 2005 | title theme unofficial soundtrack |
| "Maybe I'm Amazed" | "The OC" | 2004 | official soundtrack |
| "Just a Ride" | "The OC" "Monster-in-Law" "The Prince and Me" "Grey's Anatomy" S. 2, Ep. 2 | 2004 2005 2005 2005 | official soundtrack official soundtrack official soundtrack unofficial soundtrack |
| "They" | "Crossing Jordan" "Grey's Anatomy" S. 1, Ep. 1 "The X Effect" | 2004 2005 2007 | unofficial soundtrack unofficial soundtrack title theme |
| "Save Me" | "Grey's Anatomy" S. 1, Ep. 6 | 2005 | unofficial soundtrack |
| "Flying High" | "Wonderfalls" S.1, Ep. 11 "Grey's Anatomy" S. 2, Ep. 20 "One Tree Hill" S. 2, Ep. 15 "Laguna Beach" | 2004 2005 | unofficial soundtrack |
| "Amazing Life" | "Six Feet Under" Lexus ES 350 | 2005 2006 | official soundtrack advert |
| "24" | "Ultraviolet" "Smallville" | 2006 2005 | trailer unofficial soundtrack |
| "Once in Every Lifetime" | "Eragon" | 2006 | official soundtrack |
| "California Sun" | "Grey's Anatomy" S. 3, Ep. 22 | 2007 | unofficial soundtrack |
| "It's Amazing" | "Sex and the City: The Movie" | 2008 | official soundtrack |
| "Crazy" | "Gossip Girl" | 2008 | unofficial soundtrack |
| "I Always Knew" | "90210" | 2008 | unofficial soundtrack |


| Year | Single | Chart positions | Album | |
|---|---|---|---|---|
| UK | AUS | |||
| 2005 | "They" | 6 | 38 | Finally Woken |
| "Just a Ride" | 16 | — | ||
| "Wish I" | 24 | - | ||
| 2008 | "It's Amazing" | - | - | Down to Earth |
| "Crazy" | - | - | ||
| "I Always Knew" | - | - | ||
| Song | Production Title | Year | Production Genre |
|---|---|---|---|
| "Just a Ride" | Music from the OC: Mix 1 | 2004 | soundtrack |
| "Maybe I'm Amazed" | Music from the OC: Mix 2 | 2004 | soundtrack |
| "Amazing Life" | Six Feet Under, Vol. 2: Everything Ends | 2005 | soundtrack |
| "Easy Way Out" | Carmen Rizzo - The Lost Art of the Idle Moment | 2005 | album |
| "The Thieves" | Weapons | 2006 | album |
| "Once in Every Lifetime" | Eragon | 2006 | soundtrack |
| "Everytime" | Vusi Mahlasela - Guiding Star | 2007 | album |
| "Ecouter" | Carmen Rizzo - Ornament of an Imposter | 2008 | album |
| "It's Amazing" | Sex and the City: The Movie | 2008 | soundtrack |