Want One was the third studio album by singer-songwriter Rufus Wainwright, released in 2003 and produced by Grammy Award-winner Marius de Vries. It contains the singles "I Don't Know What It Is" and "Oh What A World". Both songs were featured in season two of the television series Nip/Tuck. The album features guest vocals by Martha Wainwright, Joan Wasser (Joan As Police Woman), Teddy Thompson, and Linda Thompson, as well as a banjo solo by Wainwright's mother Kate McGarrigle.