De Mille brought ballet form to musical comedy, using dance to enhance the plot and move the story along, first in Oklahoma! (1943), and later in such musicals as Bloomer Girl (1944), Carousel (1945), Brigadoon (1947), and Paint Your Wagon (1951). She created dances for the American Ballet Theatre, notably Fall River Legend (1948), and for films. Choreographing some 15 musicals and 21 ballets, she was a significant force in a new American realism that mingled ballet technique, vernacular movement, and modern psychology.
Although there was more sentimental pleasantness than true originality in de Mille's choreography, her works did much to popularize serious dance with the public. In addition, she was an important spokesperson for governmental and private support for the arts at congressional hearings and other public forums. In 1973 de Mille founded the Heritage Dance Theater, which was based at the North Carolina School of the Arts. A talented writer, de Mille was the author of 12 books including To a Young Dancer (1962), The Book of the Dance (1963), and Martha: The Life and Work of Martha Graham (1991).
See her autobiographies, Dance to the Piper (1952), And Promenade Home (1958), Speak to Me, Dance with Me (1973), and Where the Wings Grow (1978); No Intermissions: The Life of Agnes de Mille (1995) by C. Easton.