Kjartan "Kjarri" Sveinsson (Icelandic pronunciation: ​[ˈcʰar̥tan ˈsveinsɔn]; born 2 January 1978) is the keyboardist for the Icelandic post-rock band Sigur Rós. He joined the band in 1998. A multi-instrumentalist, he has also played such instruments as the flute, tin whistle, oboe, guitar and the banjo, as well as many of the unorthodox instruments that contribute to Sigur Rós's distinctive sound. Kjartan is a member of the advisory board for Kraumur Music Fund, which aims to "strengthen Icelandic musical life, primarily by supporting young musicians in performing and presenting their works."