A key party is a type of gathering that was supposedly popularized in the late 20th century, particularly during the 1970s and the sexual revolution. The idea is that couples (typically married couples) who attend the party would place their car keys into a bowl or a hat. At the end of the evening, the women would draw a set of keys from the bowl and go home with the man whose keys they drew, with the intention of engaging in sexual activity. Key parties are often associated with "swinging" or "wife swapping", where established couples mutually agree to swap partners for one night.
It's important to note, however, that while key parties are frequently mentioned in popular culture, there's debate about how often these types of parties actually occurred, or whether they were largely a product of urban legends and sensational media reports.
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