"(The Best Part of) Breaking Up" is a song written by Phil Spector, Pete Andreoli and Vince Poncia. It was first recorded by The Ronettes, produced by Phil Spector and arranged by Jack Nitzsche with Ronnie Spector on lead vocals and with backing vocals by Nedra Talley and Estelle Bennett, ably abetted by Darlene Love and the Blossoms, Bobby Sheen (a.k.a. Bob B. Soxx), and Sonny and Cher. The song was released in April 1964, the year widely recognized as the group's most successful year, and proved to be the group's third consecutive top forty hit in the US. The single peaked at number 39 on the U.S. Billboard Hot 100 and number 43 on the UK Singles Chart.

With the British invasion in full force during 1964, many of the previous American groups from the late 1950s/early 1960s found their popularity beginning to seriously wane. For the Ronettes, however, 1964 proved to be their biggest year. While none of their singles matched the success of their 1963 classic "Be My Baby", the group released four songs, all of which reached the top forty on the Billboard Charts in the US. Before making "(The Best Part of) Breakin' Up," their previous single had been the successful "Baby, I Love You", which peaked at number twenty-four on the Billboard charts.

However, according to Ronnie Spector, the group's lead singer, producer Phil Spector had already begun to somewhat lose enthusiasm for the Ronettes in early 1964. The group had recorded the Phil Spector, Jeff Barry, and Ellie Greenwich song "Chapel of Love" in early 1964, but Spector refused to release it. "It doesn't sound like a hit," he told the group, so The Dixie Cups recorded their version of the song, which peaked at number one on the Billboard top 100, a position never held by the Ronettes.

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