"Why Don't You Do Right?" is the song that Jessica Rabbit sings in the 1988 film "Who Framed Roger Rabbit". The song is an American blues and jazz-influenced pop song (now a standard) written in 1936 by Kansas Joe McCoy and recorded by singer Lil Green in 1941 and by Peggy Lee and Benny Goodman in July 1942, in one of the best-known versions of the song. This song has a twelve-bar minor-key blues form with a few chord substitutes.

In the film, "Why Don't You Do Right?" is sung by Rabbit at the Ink and Paint Club. Although Kathleen Turner provided the speaking voice for the character (Jessica Rabbit), the vocal performance of the song was performed by Amy Irving.

This song was well liked; "Why Don't You Do Right?" was able to reach No. 4 on the "Billboard" charts, and it reached the same position on the "Harlem Hit Parade" charts.

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