Wicked is a musical with songs and lyrics by Stephen Schwartz and a book by Winnie Holzman. The story is based on the best-selling novel Wicked: The Life and Times of the Wicked Witch of the West by Gregory Maguire, a parallel novel of L. Frank Baum's classic story The Wonderful Wizard of Oz from the perspective of the witches of the Land of Oz.

Wicked tells the story of Elphaba, the future Wicked Witch of the West and her relationship with Glinda, the Good Witch of the North. Their friendship struggles through their opposing personalities and viewpoints, rivalry over the same love-interest, their reactions to the Wizard's corrupt government, and, ultimately, Elphaba's public fall from grace. The plot is set mostly before Dorothy's arrival from Kansas, and includes several references to well-known scenes and dialogue in the 1939 film The Wizard of Oz.

The musical debuted on Broadway on October 30, 2003. It is produced by Universal Pictures and directed by Joe Mantello, with musical staging by Wayne Cilento. Its original stars were Idina Menzel as Elphaba, Kristin Chenoweth as Glinda, and Joel Grey as the Wizard. Although the production received mixed reviews and was panned by The New York Times, it has proved to be a favorite among patrons. The Broadway production's success spawned productions in Chicago, Los Angeles, London's West End, Tokyo, Melbourne, and Stuttgart, along with two North American tours that have visited over 30 cities in Canada and the United States.

The score of Wicked is heavily thematic, bearing in some senses more resemblance to a film score than a musical's score. While many musicals' scores develop new motifs and melodies for each song with little overlap, Schwartz integrated a handful of leitmotifs throughout the production. A cast recording of the original Broadway production was released on December 16, 2003, by Universal Music. All of the songs featured on stage are present on the recording with the exception of "The Wizard And I (Reprise)" and "The Wicked Witch of the East". The short reprise of "No One Mourns The Wicked" that opens Act II is attached to the beginning of "Thank Goodness". The music was arranged by Stephen Oremus, who was also the conductor and director, and James Lynn Abbott, with orchestrations by William David Brohn. The recording received the Grammy Award for Best Musical Show Album in 2005 and was certified platinum by the RIAA on November 30, 2006.