

Logo on the album cover in the font ShelleyAllegro BT Gunnarsson was replaced by Orri Páll Dýrason in the same year.

Ágætis byrjun is the band's first album to feature keyboardist Kjartan Sveinsson, and their last to feature drummer Ágúst Ævar Gunnarsson, who left the band several months after the album was released. It won numerous awards, and has appeared on multiple critics' lists of the best albums of the 2000s. According to their label Smekkleysa, the album sold 10,000 copies on its first year of release in Iceland, earning the band platinum status. It received a 2000 release in the United Kingdom and a 2001 release in the United States.

Ágætis byrjun became Sigur Rós's breakthrough album, both commercially and critically. Ágætis byrjun represented a substantial departure from the band's previous album Von, with that album's extended ambient soundscapes replaced by Jónsi Birgisson's cello-bowed guitarwork and orchestration, using a double string octet amongst other chamber elements. The album was recorded between the summer of 1998 and the spring of 1999 with producer Ken Thomas. Ágætis byrjun ( Icelandic:, A good beginning) is the second studio album by Icelandic post-rock band Sigur Rós, released on 12 June 1999.
