In 2001, Time magazine chose The Brilliant Green as one of the top ten contemporary acts outside the U.S. for their "Los Angeles" album. In 2001, Tomoko Kawase started a solo project under the name Tommy February6.
After the release of The Winter Album in 2002, the band members moved on to solo projects, but the group never officially broke up. Kawase continued as a solo artist under the names Tommy February6 and Tommy Heavenly6. Matsui also started a new project called Meister. On November 22, 2003, Kawase and Okuda announced their marriage.
On June 1, 2007, it was announced that after five years of inactivity, The Brilliant Green would be returning with a new single to celebrate their 10th anniversary. The song, titled "Stand By Me," was selected as the ending theme for the new series of TV drama, Detective School Q, which began on July 3, 2007. The comeback began in earnest on August 22, 2007, as the new single hit the stores.
The band appeared in their first proper live show since their comeback by playing at the Iwafune Mountain Cliff Stage on October 21, 2007. This performance was part of the Iwafune Cliff Stage Special 2007 with The Brilliant Green appearing alongside other musical acts including DxD, Sowelu, and Viagrade.
The second single release of their comeback, "Enemy," was released on December 12, 2007. The following single, titled "Ash Like Snow" appears as an opening theme in the anime series, Mobile Suit Gundam 00. On February 20, 2008 a compilation album titled Complete Singles Collection '97-'08 was released. The band has also mentioned in an online interview that a new studio album is currently in the works, consisting of previously unrecorded songs that were written over the previous ten years.