"Love Theme from Romeo and Juliet", also known as "A Time for Us", is an instrumental arranged by Henry Mancini (from Nino Rota's music written for Franco Zeffirelli's film of Romeo and Juliet, starring Leonard Whiting and Olivia Hussey). It was a number-one pop hit in the United States during the year 1969. It topped the Billboard Hot 100 singles chart on June 28, 1969, and remained there for two weeks; it was also his only Top Ten single on that chart.

Rearranged by Mancini, the song started competing with rock and roll songs from The Beatles and the Rolling Stones on an Orlando, Florida radio station and spread from there. It faced stiff opposition from some radio stations for being too soft. Those stations had to change their mind when the song became number one, ending the five-week run of Get Back by the Beatles as the top song.

This release also topped the U.S. easy listening chart for eight weeks where it was Mancini's sole number one on the chart.

There are two different sets of English lyrics to the song. The film's version is called "What Is a Youth?", featuring lyrics by Eugene Walter, and sung by Glen Weston. This version has been released on the complete score/soundtrack release. An alternate version, called "A Time for Us", featuring lyrics by Larry Kusik and Eddie Snyder. This version has been recorded by Johnny Mathis and Andy Williams, among others. Josh Groban performed "Un Giorno Per Noi", an Italian version of "A Time for Us".

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