A fashion week is a fashion industry event, lasting approximately one week, wherein fashion designers, brands or "houses" display their latest collections in runway fashion shows to buyers and the media. These events influence trends for the current and upcoming seasons.

The most prominent fashion weeks are held in the fashion capitals of the world, with the "Big Four" receiving the majority of press coverage being New York, London, Milan, and Paris. While the fashion scene turns more multipolar in the 21st century, other centers like Beirut, Berlin, Dubai, Los Angeles, Madrid, Monaco, Rome, São Paulo, Shanghai, Copenhagen, Sibiu and Tokyo host important fashion weeks.

The concept of fashion week began in Paris, when marketers would hire women to wear couture items in public places, from racetracks to salons. These parades (parade is "défilé in French) gradually began to become social events of their own.

Fashion week happens twice a year in the major fashion capitals of the world: New York, London, Milan, and Paris (in that order). Traditionally, fashion weeks were held several months in advance of the season to allow the press and buyers a chance to preview fashion designs for the following season. In February and March, designers showcased their autumn and winter collections. In September and October, designers showcased their spring and summer collections.

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