Smith's longest-running role is voicing Lisa Simpson on "The Simpsons". She has voiced Lisa since 1987, beginning with "The Simpsons shorts" on "The Tracey Ullman Show". Smith had initially been asked to audition for the role of Lisa's brother Bart, but casting director Bonita Pietila thought her voice was too high. Smith later recalled "I always sounded too much like a girl, I read two lines as Bart and they said, 'Thanks for coming!'" Smith was given the role of Lisa, instead. She denies rumors that she almost turned down the role, though admits she had never planned a career in voice-over work. Pietila stated that, having seen her in "Living on Salvation Street", Smith was always her preferred choice. Smith lifts her voice up slightly to perform the role. Lisa is the only regular character voiced by Smith, although in some earlier episodes, she provided some of Maggie's squeaks and occasional speaking parts. Smith has only voiced characters other than Lisa on very rare occasions, with those characters usually being some derivative of Lisa, such as Lisa Bella in "Last Tap Dance in Springfield" and Lisa, Jr. in "" (both from season 11 in 2000). Smith spends two days a week recording the show.