There are at least two Japanese bands by this name.

The first, AteLieR, formed in 1999. Members at the time included JUN (vocals, guitar, synth), YUHKI (guitar, ex-FIR~REFORLE) and HARUKI (bass). They released three CDs before YUHKI left in December of 2002 to join LIFE LINE. After one more single, AteLieR disbanded in August of 2003.

YUHKI later joined JUN in Orpheus and is currently a member of uBuGoe. See also: ＡｔｅＬｉｅＲ.

The second band was called Atelier and existed from 2006 - 2007.

Vocal: ムイナ / Muina
Guitar: 庵 / Iori
Bass: Takuya
Drum: ゆひな / Yuhina (support)

OHP

There is also another artist using a similar name: アトリエ. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.