Liv Rundgren Tyler (born July 1, 1977) is an American actress and model. She is the daughter of Aerosmith's lead singer, Steven Tyler and Bebe Buell, model and singer. Tyler began a career in modeling at the age of 14, but after less than a year she decided to focus on acting. She made her film debut in the 1994 film Silent Fall. She then appeared in supporting roles in Empire Records (1995), Heavy (1996), and That Thing You Do! (1996). Tyler later achieved critical recognition in the leading role Stealing Beauty (1996). She followed this by starring in supporting roles including Inventing the Abbotts (1997) and Cookie's Fortune (1999).

Tyler achieved international recognition as a result of her portrayal of elf princess Arwen Undómiel in the The Lord of the Rings films. She has appeared in an eclectic range of films, including the 2004 comedy Jersey Girl, the indie film Lonesome Jim (2005), the drama Reign Over Me (2007) and big-budget studio films such as Armageddon (1998), The Strangers (2008) and The Incredible Hulk (2008).

Since 2003, Tyler has served as a United Nations Children's Fund (UNICEF) Goodwill Ambassador for the United States, and as a spokesperson for Givenchy's line of perfume and cosmetics. Tyler married musician Royston Langdon of the band Spacehog in 2003; they have one son, Milo, born December 14, 2004. The couple announced their separation in May 2008.