Last year, Dani and Robert, both age 33, split after 14 years together. To many, they appeared to be typical high school sweethearts who had grown apart. This was not the case. For some time Dani had felt attracted to women. She began to crave new sexual experiences. So five years ago, Dani and Robert opened up their marriage.

First came brief stints on dating apps, which were quickly abandoned for the decidedly less turbid milieu of their friends group. Dani dated an acquaintance; they swung with another couple; that foursome eventually became a triad. And then a mutual friend rented the spare bedroom in their house. When he overstayed and began a fling with Dani, Robert wasn’t happy with the situation.

“I thought it was jealousy, that he didn’t trust men,” Dani tells me. “I was more and more liking the philosophy of polyamory and feeling polyamorous, and it was not working for me to have this blanket limitation.”

Dani eventually moved out.

I first heard about their split through office gossip. Dani’s desk sits near mine at the Portland, Oregon co-working space we both frequent. We chatted benignly about her breakup one day over lunch; the way she told it, I assumed hers to be your standard monogamous marriage heading for divorce. There was no indication she and her husband had been polyamorous: engaging consensually in multiple romantic relationships. I learned that detail months later via—you guessed it—office gossip.

Dani didn’t openly advertise her nonmonogamy to her co-workers, her neighbors or me. And neither do I.

The thing you should know about me is that I’ve edited hundreds of New York magazine’s “Sex Diaries,” a series of weekly logs detailing people’s sex lives in which extramarital partners routinely pop up. I’ve written widely on relationships, cavorted within Manhattan’s sex-positive, poly and porn scenes, and have been in both monogamous and nonmonogamous relationships. So I may qualify as one of the world’s superior lunchtime gab partners on the topic.

But Dani didn’t openly advertise her nonmonogamy to her co-workers, her neighbors or me. And neither do I. If you haven’t bedded or googled me, you wouldn’t know my relationship history. This, in a nutshell, summarizes the state of open relationships in 2019. Utterly prevalent. Vehemently unadvertised.

According to a 2016 survey published in the Journal of Sex & Marital Therapy, one in five single American adults has been in a non-monogamous relationship. Approximately five percent of people in relationships are consensually nonmonogamous at any time, excluding the additional percentage that is cheating. This means at least one person you know—a co-worker, friend or relative—has fucked multiple humans while in a relationship and with their partner’s permission. In many queer circles, consensual nonmonogamy has become so standard it may be discussed before dating or even meeting, in the form of disclaimers on online dating profiles.

Despite the one-in-five statistic, media and mainstream culture have watered down consensual nonmonogamy, commonly portraying it as an accidental threesome and minimizing how nuanced these arrangements actually are. One popular instance operates under the X Mile Rule: “Sweetie, it’s okay if you hook up on the road, but don’t bring it home.” Even more prominent (based on my experience) is the Monogamy Except…Rule: “Honey, you can occasionally go to that bathhouse (or dominatrix or BDSM club), but otherwise we are monogamous.” The most specific form of nonmonogamy may be practiced by asexuals—comprising as much as one percent of the population—who partake so their sexual partners’ desires can be fulfilled.

You can be “monogamish” (mostly monogamous with occasional excursions), “hierarchical” (maintaining primary and secondary partners) or “polyfidelitous” (faithful to more than one partner). Some lifestyles coalesce around shared responsibilities of the household, kids or caretaking; others around sex. But despite or because of nonmonogamy’s current hotness—in the pages of this magazine, Ezra Miller announced he’s polyamorous, and Scarlett Johansson proclaimed, “I don’t think it’s natural to be a monogamous person”—the lifestyle has been reduced to something kinky, easily attainable or unstructured.

Though the word polyamory originated only 27 years ago according to Merriam-Webster, we can safely date the practice to at least the 1800s.

Lital Pascar, a doctoral candidate at Northwestern University, researches media representations of nonmonogamy. “The media is hypnotized by polyamory,” she tells me. “It’s interesting how everyone is trying to sell you the same story: attractive white heterosexual couples, or even families, practicing polyamory as some naughty thing done on the side. In reality, it’s ethical, and partners are respectful of one another.”

Pascar points to an episode of Netflix’s Easy in which Orlando Bloom and Malin Akerman, playing a couple trying to spice things up, pursue a threesome. “It’s just a tool to make this couple more couple-y than ever,” she says. In other words, Easy makes nonmonogamy look palatable because it’s presented as being just like monogamy but with better sex.

Polyamory has similarly popped up as a plot device on House of Cards, Transparent, I Love Dick and The Magicians. Insecure and She’s Gotta Have It explore polyamory from black perspectives. TLC’s reality show Say Yes to the Dress recently featured a triad, and some argue that The Bachelor’s success is based on a subconscious embrace of open relationships. There are at least a dozen podcasts devoted to the topic. In 2015, poly-dating app Feeld, originally called 3nder, launched in the United States; a year later, OkCupid added an “Open to Non-Monogamy” option. (Tinder and Bumble, the leading heterosexual dating apps, have yet to jump onboard.) In 2017, The New York Times Magazine asked, “Is an Open Marriage a Happier Marriage?” and in December 2018, Quartz ran an article longer than this one headlined POLYAMOROUS SEX IS THE MOST QUIETLY REVOLUTIONARY POLITICAL WEAPON IN THE UNITED STATES.

It’s not—but a possible explanation for the extravagant headline may be that polyamory requires rigorous conversations about consent. As we know, consent is reshaping our legal, media and social landscapes. Previously, states legislated certain sex acts, relationships and marriages; before that, religious codes or childbearing needs sanctioned them. Today our laws protect sex as something practiced between consenting adults. #MeToo has expanded the notion of consent into enthusiastic consent—the idea that a partner should not only agree but be thrilled about it.

This is all to say that today’s culture is enamored with conversations about consent and relationships, and polyamory involves both. Thus polyamory has become increasingly visible—but not necessarily in a comprehensive way. What we’re seeing is just part of the story.

To understand why as a culture we’re so curious about open relationships, you need to know how we got here. The history of nonmonogamy is exceedingly checkered. Though the word polyamory originated only 27 years ago according to Merriam-Webster, we can safely date the practice to at least the 1800s.

The 2010 book Sex at Dawn, popular among non-monogamists, includes examples of ancient and tribal non-monogamy, but that history doesn’t sit well with many anthropologists who argue that some of those scenarios were less than consensual, particularly for women, and dovetailed with practices such as pedophilia. In the Victorian era, nonmonogamy popped up among groups resisting religion or the state. Mormonism was founded in 1830, and free-love groups, including upstate New York’s Oneida Community, which practiced communalism, prospered in the mid-1800s. Outside of Mormonism, though, none reached the popular consciousness as anything beyond scandal and oddity.

Around the same time, Western culture began to associate nonmonogamy with racial stereotypes: the Oriental concubine, the Muslim sheik with many wives, the African American male and his unstoppable libido. White women and the middle class were portrayed as boring and uptight.

The next century presents a cycle of nonmonogamy squeaking into popular consciousness, only to be overshadowed by international events and shifts in cultural mores. In the 1920s, free-love movements flared among flappers owning their sexuality, but the Great Depression snuffed out sexual expression. As newspapers depicted starving families and death through World War II, sexual freedom seemed frivolous. Post-war America, of course, marked another era of sexual repression.

By the 1960s and 1970s, swinging became prevalent enough to serve as a plotline in the 1969 Natalie Wood vehicle Bob & Carol & Ted & Alice, which finished as one of the year’s highest-grossing films. Although swinging is now remembered as sex parties for multiple couples, it once involved highly organized communities that emerged only when women became aware of their right to pleasure—and their right to leave. “Swinging was a way to save the couple,” says Pascar. “It came with rules so the husband and wife wouldn’t develop relationships with anyone else. It allowed the woman just enough freedom so the couple wouldn’t fall apart.”

Swinging vanished in the face of 1980s conservatism. The Reagan administration hawked family values, with the president letting us know that “all great change in America begins at the dinner table.”

In 1981, U.S. hospitals began reporting cases of terminally ill gay men. Overnight, public interest in nonmonogamy flatlined. Communities tunneled underground as the public began to blame the sexually adventurous for the AIDS crisis. (As we now know, closed-circle nonmonogamy poses no greater risk than monogamy of sexually transmitted infections. Terri Conley, an associate professor of psychology at the University of Michigan, says research indicates that most STIs come from close partners, not casual ones, because the latter practice safer sex.) As panic spread, many non-monogamists either went monogamous or mute, making it difficult for newcomers to find like-minded people.

For this reason, little has been reported on the non-monogamous culture of the 1980s. As 52-year-old Carlos Peñaranda remembers of the response to the AIDS epidemic within the gay community, “Nonmonogamy was generally not announced because of that whole stigma of slut-shaming and ‘Oh, you’re sleeping around, so you’re just asking to get STDs and AIDS.’ ”

Many sex researchers lost funding as attention turned to HIV and AIDS and the intimate relations of gay men. Bisexual men also came under scrutiny out of concern they could spread HIV to unknowing wives. Gay male relationships shifted profoundly, now needing to meld caretaking with romance and familial bonding.

Meanwhile, straight nonmonogamy remained nearly absent from mainstream arenas, social or academic. “Sexuality studies in general experienced a significant chilling with the George H.W. Bush administration,” says sociologist Eli Sheff, an educational consultant and respected pioneer in polyamory research. “They very much wanted to fund Christian things, so even AIDS research was out of vogue, and sex positivity was not going to fly.” (Not that things are dramatically better now: In 2011, Sheff’s own career became a cautionary tale when she was denied tenure at Georgia State University because of her lack of grant funding; she has been a visiting professor ever since.)

A well-known, large-scale survey of U.S. sexual behaviors, The Social Organization of Sexuality, by sociologists at the University of Chicago, launched with the hope of support from the National Institutes of Health, but the U.S. Senate, led by conservative stalwart Jesse Helms, denied funding. Named a New York Times Book Review “notable book of the year” upon its eventual release in 1994, the book of the same name is still illuminating: Religious people had just as many recent sex partners as the nonreligious, and people in conservative areas had the same transgressive urges as everyone else, though they were less likely to act on them.

Internet groups led to “coherent identities and more shared understandings of how to do open nonmonogamy.”

This brings us to the first known uses of the word polyamory. The earliest may be in a 1990 essay called “A Bouquet of Lovers: Strategies for Responsible Open Relationships” by Morning Glory Zell-Ravenheart. An online forum called alt.polyamory appeared in 1992. In-person meet-ups, such as the Loving More Conference, followed, spurring a new wave of community. As with other marginal groups, the internet allowed people to connect, and polyamory thrived.

The Ethical Slut, a 1997 book that describes how to be caringly promiscuous, became a bible of sorts. Meg-John Barker, a longtime researcher on nonmonogamy and a senior lecturer in psychology at the U.K.’s Open University, says such codifying books and internet groups led to “coherent identities and more shared understandings of how to do open nonmonogamy, with practices becoming more nuanced, sophisticated and diverse.” The Polyamory Leadership Network, “a loose association” of about 180 activists, launched online in 2008 and has since created an “accountability pod,” to collect stories of problematic behavior, and a “survivor support pod,” focused on victims.

In short, communities helped polyamory develop a lexicon. Smart people once again began to keep tabs, legitimizing the lifestyle. The first European conference devoted to non-monogamy, the International Conference on Polyamory and Mono-Normativity, convened in 2005. Universities began to extend funding again. Conley says she told faculty interviewers at the University of Michigan that her research was “not really fundable, so if I need big grants to get tenure, we can all just go home.” They hired her. She’s now among the top researchers in the field.

She became poly solo, a term for dating multiple lovers while maintaining one’s own finances and home.

After leaving Robert, Dani moved into her own apartment and studied More Than Two: A Practical Guide to Ethical Polyamory, a popular read among newcomers. She wishes she had consulted it earlier. While most polyamory beginners hurt people accidentally, she found herself bewildered by a larger shift in her identity. “It was confusing for me, because while I wanted to open up romantic relationships, I realized I also wanted to just be more physical, like with friends. Sitting closely or having our arms around each other or even holding hands—I wanted to be more warm,” she says.

Dani had entered polyamory expecting it to be about fucking but found a new way of thinking altogether: primarily, that relationships can be fluid. This made her reassess the boundaries around her other relationships. She became poly solo, a term for dating multiple lovers while maintaining one’s own finances and home. Her new girlfriend “took to polyamory like water,” she says.

Some forms of nonmonogamy have better odds of success than others. Conley’s studies show that swinging and polyamorous relationships do “just as well or better” than monogamous relationships in categories including trust, overall satisfaction, commitment, satisfaction with last encounter and rate of orgasm. But when Conley asked a group of her graduate students whether everyone should practice consensual nonmonogamy, the answer was a unanimous no. “They had read the research,” she says. To sum up, dating and sex take time and emotional energy—a lot of emotional energy—and intensive processing. “It’s perfectly reasonable that most people would be monogamous in our current societal structure. It’s a lot simpler to navigate life,” she says. Allow me to add another downside: Polyamory’s emphasis on meeting one’s own needs can translate into narcissism.

Dani discovered the complexities of nonmonogamy experientially. After seven months apart, she and Robert reconciled. They now keep separate homes and identify as polyamorous.

For most straight younger people today, the popular form of non-monogamy is nonhierarchical polyamory, according to More Than Two. (At 496 pages, the book is far from comprehensive: “We didn’t include things like what to do if a partner breaks an agreement,” co-author Franklin Veaux says.) Different from the stability of “anchor partners,” the cornerstone of nonhierarchical polyamory is egalitarianism. A partner of 20 years, for example, does not outrank a new flame. This scenario is the antithesis of arrangements in which primary partners have veto power over other partners.

Gay men tend to distinguish sexual partners from romantic ones. Peñaranda and his husband, Daniel Leyva, decided to open their relationship after six years of monogamy. Leyva is 17 years Peñaranda’s junior; this marriage is his first gay relationship. Peñaranda, who had always practiced monogamy, was not initially thrilled about the prospect of opening up. “I had gotten hurt a number of times with guys stepping out on me when we were supposed to have a monogamous relationship, and I didn’t want that to be the case here,” he says. “But Daniel is young. He wanted to experience things.”

Note that Peñaranda’s decision was based not on promiscuity but on preserving his relationship. That was also the case for Dani and Robert. Nevertheless, jealousy often arises.

“We laid down some ground rules,” Peñaranda says. “We always have to be honest with each other and put each other first. No romantic dates. We’re each other’s number ones. There have been a few times we’ve said, ‘I’m not exactly feeling like number one right now,’ and we backtrack and fix it.”

Peñaranda and Leyva got prescriptions for Truvada, a pre-exposure prophylaxis (or PrEP) that reduces the risk of HIV transmission. The rise of PrEP (which can be prescribed across the gender spectrum) has allowed gay men to have more casual sex, though gay and bisexual men on PrEP are 72 percent more likely to get STIs than gay and bi men not on the medication, according to a 2018 study published in the journal AIDS. When it comes to STIs, volume matters: Having unprotected sex with more than five partners a year increases STI risk significantly.

Like Dani and Robert, Peñaranda and Leyva began their open relationship by using dating apps, which procured them a group of friends with benefits. “We go to pool parties and stuff that are not called sex parties, but sex happens there. They always have a play area,” Peñaranda says. As often happens in open relationships involving well-known play partners—or people with whom one has sexual relations often—the rules slowly began to lift. The limitations Peñaranda gave Leyva regarding certain sex acts disappeared. “Now he can go have whatever fun he wants,” Peñaranda says nonchalantly.

Yet gay nonmonogamy, like straight nonmonogamy, continues to be an open secret, even with more of the population participating. (A 2016 U.K. survey by gay men’s health charity GMFA reported more than 40 percent of its 1,006 gay respondents had been in an open relationship.) “Even now I don’t go, ‘Hi, I’m in an open relationship,’ ” says Peñaranda. “I’m very protective of Daniel and of our lives, so I pick and choose who I let know.”

“This creates a public silence about what’s really going on. The public version is different than the practice.”

As director of prevention research at the Ontario HIV Treatment Network, Barry Adam has “interviewed sizable numbers of couples who, it turns out, have other partners—a third person or individual additional partners.” But, he says, “even within those communities, there isn’t much talk about it.” He suggests the cultural adoption of gay marriage may have stymied frank conversations, because society presumed gay marriages were monogamous, as that’s the presumption built into heterosexual marriages. “This creates a public silence about what’s really going on,” Adam says. “The public version is different than the practice.”

Despite increasing interest, polyamory is far from accepted. Polyamorists can be fired by companies with morality clauses. “There are very few legal protections for openly nonmonogamous people, or ways of having their relationships recognized,” says Barker. Even Sheff, who writes a column for Psychology Today called “The Polyamorists Next Door” and who does not identify as polyamorous, has faced professional blowback regarding her polyamory research. “I’ve had quite a few people question my science in a very aggressive way. It’s as though they feel personally attacked. Maybe their dad cheated on their mom, or they’re cheating right now and have personal issues around it.”

Amy Moors, an assistant professor of psychology at Chapman University, studied Google searches from 2006 to 2015. She found that searches for polyamory have increased significantly since 2011. Barring an international crisis, we can expect nonmonogamy to continue to evolve—and be fetishized—though it’s far from being widely embraced. Generation Z likely won’t adopt it as a dominant lifestyle choice (the way putting off marriage is now popular among millennials, for example), but the next wave in the dating pool—and Generation Alpha—may be willing to consider more relationship varieties en masse. As research indicates, monogamy doesn’t work for everyone, nor does it work all the time. At minimum, a seat at the table for consensual non-monogamy raises the possibility of gabbing about it with co-workers at lunch. Maybe then we’ll all finally start talking about it together.