The Daihatsu Sirion is a subcompact car produced by the Japanese automaker Daihatsu since 1998. Various versions of the Sirion have also been known as the Daihatsu Storia and Boon, and the Toyota Duet and Passo.
The Sirion was launched in 1998 and has since undergone two upgrades, one in 2001 and another in 2004/2005. The version of the Sirion on sale in Europe and Australia in 2005 was first released in Japan in June 2004 under the names Daihatsu Boon and Toyota Passo.