Ralph Nelson was an American film and television director, producer, writer, and actor. He was best known for directing Lilies of the Field (1963), Father Goose (1964), and Charly (1968), films which won Academy Awards.

Lilies of the Field is a 1963 American comedy-drama film adapted by James Poe from the 1962 novel of the same name by William Edmund Barrett, and stars Sidney Poitier, Lilia Skala, Stanley Adams, and Dan Frazer. It was produced and directed by Ralph Nelson. The title comes from the Sermon on the Mount in the Bible. It features an early film score by prolific composer Jerry Goldsmith. The film was turned into a Broadway musical in 1970, retitled Look to the Lilies, with Shirley Booth in the role of Mother Maria Marthe.