Brian and his wife, both in their early forties, like to meet new couples privately over dinner and drinks to talk and gauge mutual interest in trading partners for sex. He’s been swinging for ten years. “I’m very happily married,” he says. So why the interest in this activity? Married swingers aren’t looking for affairs or romantic ties outside their home; they want sex with different partners—and the endorsement of their significant other. Consensual, recreational sex within the confines of matrimony.

The allure of swinging isn’t so much sex with someone new but that “vibe in the air which adds to an encounter,” he says. “It’s a feeling most people haven’t had since they were 17 and trying to get to second base. You don’t know how the night is going to end.”

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“Let’s face it, it’s easy for a married couple to fall into a day-to-day rut. Work, kids, house chores, bills, repeat…,” Brian says. Swinging adds some excitement to the ins and outs of everyday life. And with the ease of finding information and partners online (Brian runs the website www.theswingscene.com) and changing attitudes about monogamy, more people may be taking the plunge, says Curtis Bergstrand, a sociologist at Bellarmine University in Louisville, Kentucky, and the author of “Swinging in America: Love, Sex and Marriage in the 21st Century.”

There are many variations on open relationships besides swinging. According to a review by psychologists Meg Barker and Darren Landridge of the Open University in England,“open relationships” tend to refer to gay pairs that permit both partners to play around without getting too emotionally involved. “Polyamorous” couples embrace more than one romantic relationship at a time. Swingers mostly do their extra-marital playing together as a couple and make sure to keep things light and fun.  Depending on whom you ask, a heterosexual “open marriage” could be poly or swinging or some arrangement unique to the couple.

The Basics

 Swinging comes in many different forms. “Soft swap” couples engage in all sorts of fun except swapping partners for intercourse; “full swap” goes all the way. Some stipulate “same room only” play; others are okay with seeing their partner go off into another room for some privacy. Some don’t allow open-mouth kissing (considered more intimate than sex). Some go to public swing events; others meet with only one other couple at a time.

Swinging can also be expensive, according to research by Fabio D’Orlando, an economist at the University of Cassino in Italy. Couples buy sexy clothing, meet with other couples in fancy restaurants, or splurge on pricy adults-only resorts like Hedonism in Jamaica.

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Taking Precautions

To protect their privacy, many swingers don’t post photos on their public online profiles. So what happens if you see your boss’s boss at a swinging event? Well, he’s vulnerable, too. Although on occasion people do get outed, being indiscreet is a “sure way to get yourself blacklisted from the community,” Brian says. “You will see all shapes, sizes and races at events and clubs,” he continues, but just like dating, swingers are looking for matches who are roughly as attractive as themselves: “You will usually see the 8’s paired up with the 8’s and the 3’s with the 3’s.”

Being ethical and talking about safe sex and STDs is also a part of the drill. Dan, a 52-year old swinger from New Jersey, has herpes and is careful to disclose the risks to new partners. Even with condoms, swingers risk picking up viruses like herpes and HPV (human papillomavirus), a precursor that can lead to cervical and throat cancers.

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Not surprisingly, swingers develop more STDS than non-swingers, especially if they’re older women, according to a 2010 study of visitors to a Dutch clinic that provides free screening and treatment. Among straight women over the age of 45, 17.9 percent of the swingers tested positively for chlamydia, gonorrhea, or both, (compared to only 4 percent of women who didn’t swing). Of the straight male swingers in that age group, 10.4 percent tested positively for those diseases (compared to 2.4 percent of non-swingers).

Marriage Maker or Breaker?

 Observers say this lifestyle won’t save a bad marriage, but it can help a couple through a sexual dry patch. Brian believes that couples who swing well are big communicators: “They are each other’s best friend and tend to tackle things, whether recreational or serious, as a true team.”

“I’ve never heard anyone say that swinging improved their marriage,” says relatioship expert and author of “The Breakup Bible,” Rachel Sussman. But she’s noticed that swingers tend to begin their relationship with a “open attitude to sex” and may have started swinging early on. The key, she says, is to establish “hard and fast rules” before you go to swinging events: what can each person do?

Even though many people assume that swinging is a man’s fantasy, it’s often the women who find themselves enjoy it more, Bergstrand says. Men are more likely to feel competitive with other men, wondering if their wives preferred their swinging partners, while women tend to be supportive of each other within the swinging scene, he says.

QUIZ: Are You Sexually Satisfied?

The Bottom Line 

Although there’s little research on swinging, Bergstrand conducted an online survey in 1999, speaking with over 1000, self-identified swingers to determine if swinging was a more modern alternative to monogamy. What he found was that those living the swinging lifestyle were predominantly white, semi-educated, 40 years-old on average, nor do they possess any particular history of sexual abuse or any other special psychological profile.

Like Brian, “they see it see it as way to introduce excitement back into their marriage,” Bergstrand says. These couples are “very much in love, and have lots of trust,” he adds. “They separate love from sex when they swing. Sex is just recreation.”