"Rich Girl" is a song by Daryl Hall and John Oates. It debuted on the Billboard Top 40 on February 5, 1977 at number 38 and on March 26, 1977, it became their first (of six) number-one singles on the Billboard Hot 100. The single originally appeared on the 1976 album Bigger Than Both of Us. At the end of 1977, Billboard ranked it as the 23rd biggest hit of the year.

The song's lyrics are about a spoiled girl who can rely on her parents' money to do whatever she wants. The song was rumored to be about the then-scandalous newspaper heiress Patty Hearst. In fact, the title character in the song is based on a spoiled heir to a fast-food chain who was an ex-boyfriend of Daryl Hall's girlfriend, Sara Allen. "But you can't write, 'You're a rich boy' in a song, so I changed it to a girl," Hall told Rolling Stone.

Hall elaborated on the song in an interview with American Songwriter:

"Rich Girl" was written about an old boyfriend of Sara [Allen]'s from college that she was still friends with at the time. His name is Victor Walker. He came to our apartment, and he was acting sort of strange. His father was quite rich. I think he was involved with some kind of a fast-food chain. I said, "This guy is out of his mind, but he doesn't have to worry about it because his father's gonna bail him out of any problems he gets in." So I sat down and wrote that chorus. [Sings] "He can rely on the old man's money/he can rely on the old man's money/he's a rich guy." I thought that didn't sound right, so I changed it to "Rich Girl". He knows the song was written about him.

Several years later, Hall read an interview with David Berkowitz, the Son of Sam killer, in which Berkowitz claimed that "Rich Girl" had motivated him to murder (although the song was not released until after the Son of Sam murders had already begun, casting doubts on that suggestion). Hall & Oates later reflected this disturbing fact in the lyrics of the song "Diddy Doo Wop (I Hear Voices)" on the album Voices.

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