I was three hours into a Tinder date recently when the man mentioned that he had a long-term girlfriend. They’d been living together, in an ethically non-monogamous partnership, for 10 years. I was surprised, but not shocked—since joining Tinder eight months ago, I’d encountered (and admittedly scrolled past) many non-monogamous people. But unlike them, this guy hadn’t mentioned it on his profile. Instead, he’d implied by omission that he was single.

“Non-monogamy is a vague term,” says Shannon Chavez, Psy.D, a clinical psychologist and licensed sex therapist. “You can have 10 people in a room, and they all practice it differently, which can get confusing.” But usually, it implies that you have one “primary” relationship and then one or more “secondary” partners—compared to polyamory, which tends to mean you are involved in multiple couplings of the same intensity.

Alan*, 51, says non-monogamy for him always involves transparency. “All my dating app profiles say, ‘My wife knows I’m on this site, and I know about her relationships,’” he says. His 28-year marriage has been “monogamish,” as he calls it, for about a year. He meets women on Tinder and Bumble, while his wife is involved on a more long-term basis with both members of a couple they’re friends with. Alan says the arrangement has saved their marriage.

“Without the rigid structure of monogamy, you really have to hear, understand, and accommodate everybody’s needs.” —Alan, a man in a monogamish marriage

He may be on to something. A 2017 study in Perspectives on Psychological Science found that people in open relationships report more trust and less jealousy than monogamous partners. Specifically, exclusive couples reported much higher rates of “anticipated sexual jealousy”—imagining a partner being attracted to, and maybe even sleeping with, someone else. In open relationships, both partners take both of the above as a given, which removes that element of fear from the equation. The study also suggests that a non-monogamous lifestyle teaches partners how to handle jealousy in a healthier way.

Alan says his new arrangement with his wife has made him a better listener, not just to her, but to the women he dates as well. “Without the rigid structure of monogamy, you really have to hear, understand, and accommodate everybody’s needs,” he explains. “Otherwise, it doesn’t work.”

There’s also growing evidence that people in open relationships aren’t just happy and healthy (as a study released this past March shows) they’re happier and healthier than their monogamous counterparts—at least those over the age of 55. In a different study from 2014, non-exclusive “aging adults” (as they’re called in the study) were found to have sex more frequently, report higher sexual satisfaction, and get tested for HIV more regularly. Respondents to the survey also reported being significantly happier than the general population and more satisfied with their relationship than monogamous couples.

There’s also growing evidence that people in open relationships aren’t just happy and healthy, they’re happier and healthier than their monogamous counterparts.

When Dr. Chavez counsels couples who are considering opening their relationship, one partner often seizes on the emotional element. “One of them says, ‘I have this fear that my partner might fall in love with someone else and then leave me.’” It seems valid—and there are certainly examples of this happening—but the 2017 study actually shows the opposite. Non-monogamous people with two partners feel more satisfaction, trust, commitment, and passionate love in their primary relationship than in their secondary.

That’s good news for the couple—but maybe not great for the “extra” people that each member of the couple dates. That all depends on what that person’s looking for. In this regard, it seems Alan is onto something with his openness about his open relationship. For folks looking to date casually, having healthier, happier, better listeners in the dating pool is great. But when you’re looking for something more, or if you enter an open relationship unwittingly, trouble can understandably arise.

That’s what happened to Beth R., 28. In her early twenties, she learned that her monogamous boyfriend of two years had cheated on her. When she confronted him about it, he told her that she couldn’t blame him for being polyamorous. “It was the first time he said anything to me about being poly, and that didn’t change the fact that we were monogamous at the time,” says Beth. “I got the sense he was trying to use it the label as an excuse for cheating.”

Dr. Chavez concurs that the looseness of these terms makes them easy for some people to abuse. If you suspect that someone’s using ethical non-monogamy as a cover to avoid committing to you, she suggests asking questions about how they practice these values early on. “If they don’t describe their lifestyle in a way that’s clear and consistent, that could indicate they’re masking more general commitment issues.”

The growing ubiquity of “alternative” levels of commitment is also making more single people consider what we actually value in a relationship.

Monogamy has always been the cultural expectation for most of us—single women in particular. Five years ago, I would have gotten pitying looks from friends if I mentioned that I was dating a guy who proclaimed to be non-monogamous, even if I wasn’t interested in an exclusive relationship with him either. But couples aren’t the only ones allowed to make their own rules.

The growing ubiquity of “alternative” levels of commitment is also making more single people consider what we actually value in a relationship. “Lately, people have been coming to me wanting to examine their idea of monogamy,” says Dr. Chavez. “Sometimes, once we’ve talked through it, they realize they’re looking for intimacy or connection—and the exclusivity element actually isn’t important to them.”

In other words, whether or not ethical non-monogamy is for you, its existence is making us all date more mindfully.

*Name has been changed

Whether you want to be monogamous or monogamish (or something else entirely!), it’s important to talk about it early on. Here’s why the DTR talk is key to having a healthy relationship. And if you’re looking for love online, these are the red flags that warrant a left swipe.