Online dating service OKCupid now makes it easier for its users to date multiple people, including married people. The site will allow couples who say they’re “seeing someone,” “married” or “in an open relationship” to invite other users to join that relationship.

OKCupid says it’s merely responding to what its users want: It has found that nearly a quarter of its users are interested in group sex (up from 16% in 2010), and 42 percent say they’d consider dating someone in an open relationship. Meanwhile, users who said they’d be interested in only a monogamous relationship fell to 44 percent, down from 56 percent five years ago.

“We saw a need coming from current users in non-monogamous relationships and we identified that there was a trend toward more openness, and even curiosity, regarding non-monogamous and open relationships,” says Jimena Almendares, OKCupid’s chief product officer. (Time)