Group sex is sexual behavior involving more than two participants. Participants in group sex can be of any sexual orientation or gender. Any form of sexual activity can be adopted to involve more than two participants, but some forms have their own names.
Group sex most commonly takes place in a private sex party or semi-public swinger gathering, but may also take place at massage parlors or brothels or, in some jurisdictions, at purpose-built locations such as sex clubs. In places where non-monogamous sex is taboo or illegal, group sex may take place in private or clandestine locations including homes, hotel rooms, or private clubs.
Fantasies of group sex are extremely common among both men and women. Many forms of sexual behavior were reported by Kinsey's subjects, but the official Kinsey Reports website does not mention threesomes or group sex in the summary of Kinsey's findings.
Group sex is a subgenre in pornographic films.