"Dancing Queen" is a Europop song by the Swedish group ABBA, and the lead single from their fourth studio album, Arrival. It was written by Benny Andersson, Björn Ulvaeus and Stig Anderson. Andersson and Ulvaeus also produced the song. "Dancing Queen" was released as a single in Sweden on 15 August 1976, followed by a UK release and the rest of Europe a few days later. It was a worldwide hit. It became ABBA's only number one hit in the United States, and topped the charts in Australia, Belgium, Ireland, Mexico, New Zealand, Norway, South Africa, Spain, Sweden, the United Kingdom, West Germany and Zimbabwe. "Dancing Queen" also reached the Top 5 in many other countries.

Musically, "Dancing Queen" is a Europop version of American disco music. As disco music dominated the US charts, the group decided to follow the trend, replicating Phil Spector's Wall of Sound arrangements. The song alternates between "languid yet seductive verses" and a "dramatic chorus that ascends to heart-tugging high notes." It features keyboard lines by Andersson, which accentuate the melody's sophistication and classical complexity, while Ulvaeus and Andersson interlace many instrumental hooks in and out of the mix.Anni-Frid Lyngstad and Agnetha Fältskog's layered vocals have been noted for their dynamism, "[negotiating] the melody's many turns flawlessly." Lyrically, the song concerns a visit to the discotheque, but approaches the subject from the joy of dancing itself, thus having a greater emotional content than that of many other disco songs.

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