Yeardley Smith (b. 1964) is an actress and voice performer best known for providing the voice of Lisa Simpson on the animated series The Simpsons. In 1991, she reprised the role, along with her co-stars, in the celebrity version of "Monster in the Mirror." She also voiced narration for interactive storybook version of Too Big for Diapers for the 2006 Elmo's Potty Time DVD.
Earlier in her career, Smith guest starred on CTW's Square One TV as gorilla activist Jane Rice-Burroughs. Other credits have included parts in the films Maximum Overdrive (with Pat Hingle) and Toys (with Robin Williams). On TV, she was a regular as Louise on the sitcom Herman's Head, recurred on Dharma & Greg, and made guest spots on Murphy Brown and The Big Bang Theory.