Rachel Anne Griffiths AM (born 18 December 1968) is an Australian film and television actress. She came to prominence with the 1994 film Muriel's Wedding and her Academy Award nominated performance in Hilary and Jackie (1998). She is best known for her portrayals of Brenda Chenowith in the HBO series Six Feet Under and Sarah Walker Laurent on the ABC primetime drama Brothers & Sisters. Her work in film and television has earned her a Golden Globe Award, two Screen Actors Guild Awards and three Australian Film Institute Awards.

Griffith attended Melbourne University, studying philosophy, before attending the drama department at Victoria School of the Art.  After college, she began working with the touring youth company Woolly Jumpers Theater Company, as well as the Melbourne Theater Company, where she appeared in numerous dramas.