Valgeir Sigurðsson (born 18 June 1971) is an Icelandic record producer, mixer, composer, audio engineer and musician.

He plays keyboards, bass, percussion, electronics/programming and studied classical guitar, graduating with a Tonmeister degree from London's SAE Institute.

In 1998 Valgeir was hired by fellow countrywoman Björk as engineer and programmer on the soundtrack for Lars von Trier's Dancer in the Dark.

His working relationship with Björk continued beyond the film project and was consistent from early 1998 until 2006, during which time Valgeir was one of her main studio collaborators.

Valgeir is the founder of Greenhouse Studios, Iceland's top recording facility established in 1997, where in addition to Björk, he has collaborated with artists such as Bonnie 'Prince' Billy, Feist, Damon Albarn, Camille, CocoRosie, Ben Frost, Sam Amidon, múm, Hilary Hahn & Hauschka, Brian Eno, Sigur Rós, Emel Mathlouthi,[2] and many others.