"It's My Party" is a pop song recorded by multiple artists since the 1960s. In 1963, American singer Lesley Gore's version hit #1 on the pop and rhythm and blues charts in the United States. It was the first hit single for producer Quincy Jones.

The song lyrically portrays the discomfiture of a teenage girl at her birthday party when her boyfriend Johnny disappears, only to surface in the company of Judy, another girl, who is "wearing his ring," to indicate she's replaced the birthday girl as his love interest.

The song's chorus, "It's my party, and I'll cry if I want to... You would cry too if it happened to you!" became a part of American pop cultural language as a phrase used to describe being utterly humiliated and miserable during an event that is supposed to be a happy occasion.

"It's My Party" is in the key of A major. The song's effectiveness is enhanced by several musical touches producer Quincy Jones incorporated, including Latin-sounding rhythms, double tracked vocals and effective horn parts.Allmusic critic Jason Ankeny wrote of the song, "'It's My Party' remains one of the most vivid evocations of adolescent heartbreak ever waxed — Quincy Jones produced the record, although you'd swear it was Aaron Spelling instead."

"It's My Party" was credited to John Gluck, Wally Gold and Herb Weiner, staff writers at the Aaron Schroeder Music firm in 1962. The lyrics were actually written by Seymour Gottlieb, a freelance songwriter. He gave the lyrics to Herb Weiner, with whom he partnered in writing songs, to peddle. It was based on actual events relating to Gottlieb's daughter Judy's ‘Sweet 16’ party, before which she cried over the prospect of her grandparents being invited. The demo for the song was cut by Barbara Jean English, a girl group veteran (the Clickettes, the Fashions), who was then working as a receptionist at the firm. She also worked with Jimmy Radcliffe, serving as the firm's in-house demo singer. Radcliffe produced the demo, and, according to English, "tried to persuade Musicor [the label owned by Aaron Schroeder] to release it as a record, or to take me into a master studio and redo it, but they weren't interested."

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