Similarities between "West Side Story" and "Romeo and Juliet" include the central conflict, the setting where the two main characters meet, the balcony scene and the violent conflict between the characters. Like "Romeo and Juliet", "West Side Story" is about the forbidden love affair between two teenagers.
Tony takes the place of Romeo in the contemporary play, while Juliet is paralleled by the character Maria. Tony is a member of the Jets street gang in New York City, and Maria is the sister of the leader of the Sharks. The two gangs loath one another. This mirrors the relationship between the Capulets and the Montagues of "Romeo and Juliet."
Tony and Maria meet at a dance just like Romeo and Juliet, who meet at the Capulet ball. In both plots, the young couple fall in love even though their respective groups are locked in enmity. The balcony scene from Shakespeare's "Romeo and Juliet" is also present in "West Side Story", although interpreted somewhat differently. In "West Side Story", the stone balcony of a castle is replaced with a fire escape.
The violent confrontations between the characters of "West Side Story" also reflect those found in "Romeo and Juliet." In the Shakespeare play, Tybalt kills Mercutio, and Romeo in turn kills Tybalt. In "West Side Story," the character Bernardo kills Riff, the best friend of Tony, which leads to Tony killing Bernardo.