Open relationships and polyamory: what the research shows and what a couple should ask

“What would you say if we tried an open relationship?”

The question comes while they are washing up, almost in passing. As if they were choosing a holiday destination. She freezes for a moment with a plate in her hand. She doesn’t know what hit her harder: the question itself, or the fact that her partner has clearly been carrying it around for a while. Ten thoughts line up in her head at once. Doesn’t he love me any more? Is there someone already? Am I not enough? And somewhere at the very back, quietly: have I ever thought about this too?

People talk about open relationships and polyamory more than they did a decade ago — in podcasts, series, on social media. But a louder conversation is not necessarily a more thoughtful one. It often splits into two camps: those who see non-monogamy as moral decay, and those who see it as liberation from an outdated model. In this article I won’t argue for either. What interests me is what the research shows, and which questions a couple can ask themselves before deciding anything.

What we are actually talking about

For relationships in which partners explicitly and mutually agree that they may have sexual or romantic contact with others too, researchers use the term consensual non-monogamy. The key word is consensual: everyone involved knows and agrees.

Several quite different forms sit under this label:

• An open relationship — the couple remains the emotional core, while sexual contact outside the relationship is permitted by agreement, often with rules about what is and isn’t allowed.
• Swinging — the couple seek contact with others together, often in a social setting, and experience it as something shared.
• Polyamory — the possibility of several romantic, not only sexual, relationships at the same time, with the knowledge and consent of everyone involved.

All of these are clearly distinct from infidelity. Infidelity isn’t about the number of partners but about breaking an agreement — about secrecy and deception. A couple in an open relationship can experience infidelity if one partner breaks the agreed rules. A monogamous couple, on the other hand, doesn’t experience it as long as both keep to their agreement.

How many people actually live like this? Reliable figures are hard to come by — people are reluctant to talk about it in surveys, and samples are often collected online. One of the more frequently cited studies is the 2017 work by Haupert and colleagues. In two large national samples of single Americans, they found that in both samples more than one in five said they had at some point in their lives been in a consensually non-monogamous relationship.

That figure is about experience at any point in life, not about how many people live this way today. It is also about single American adults, not Slovenia, for which I know of no reliable data. But it says something that often gets lost in public debate: this is not a phenomenon on the far fringes, to be talked about only as something exotic.

Stigma: what we think before we know

The psychologist Terri Conley and her colleagues, among them Amy Moors, studied how people see couples in consensually non-monogamous relationships. Participants rated them considerably worse than monogamous couples — not only on traits related to the relationship, such as trust and satisfaction, but also on traits that have nothing whatsoever to do with love. As if the label “non-monogamous” coloured everything we think about a person.

In a 2013 review, the same research group questioned several taken-for-granted assumptions about monogamy: that in itself it guarantees more trust, less jealousy and safer sex. One of their studies, for example, showed that people who cheat on their partners use protection less consistently than people in openly non-monogamous relationships. This doesn’t mean non-monogamy is safer than monogamy. It means monogamy on paper and monogamy in practice are not always the same thing.

Stigma has consequences. People in these relationships often keep quiet about them in front of family, colleagues, sometimes even their doctor. Which means they are often alone with the difficulties every relationship has.

What the research shows about satisfaction

The most common question is a simple one: are people in these relationships happy? In 2015 the psychologists Rubel and Bogaert reviewed the research on psychological well-being and relationship quality among people in consensually non-monogamous relationships. They found that on most measures they did not differ significantly from people in monogamous relationships.

Caution is needed in both directions here. On the one hand, this finding refutes the belief that every such relationship is doomed, or that only people who can’t form attachments choose it. On the other, it doesn’t mean opening a relationship is a neutral decision that will turn out well for everyone. The research mostly covers people who are in such relationships and volunteer to take part. Those whose attempt to open up ended in pain or a break-up are probably under-represented. Most studies are also cross-sectional — they describe a single moment, not a couple’s path over the years.

What the research can say reliably is more modest: the form of a relationship does not, in itself, predict happiness. What matters is how the couple look after the agreement, trust and each other.

Jealousy doesn’t disappear

One misconception found on both sides is that people in open relationships aren’t jealous — either because they are “enlightened” or because they don’t care. Jealousy is an emotion almost everyone knows, whatever the form of their relationship. I explained what it is and where it comes from in Jealousy in a relationship: when it is a signal and when it is an old wound, and you will also find a short explanation in the knowledge base under jealousy.

The difference lies not in whether jealousy appears, but in how the couple understand it. In a monogamous relationship we often read jealousy as a warning that someone has broken the agreement. In a consensually non-monogamous one, the agreement hasn’t been broken — jealousy appears even though something is happening that you agreed to. Then you can’t resolve it with an accusation, only with a question: what is speaking up in me right now? Fear of being replaced? A sense that I matter less? An old wound from childhood, when I had to share attention?

Polyamorous communities have also adopted a word for the opposite experience — compersion, joy at seeing your partner happy with someone else. It is interesting because it shows how very different emotions can arise from the same situation. But it isn’t an obligation. If you don’t feel it, that doesn’t mean you have failed at something.

Agreements: what a couple actually do

Couples who open their relationship usually agree on rules. What is allowed and what isn’t. Whether they talk about other encounters or not. Whether friends and acquaintances are off limits. Where the limits lie regarding time, staying overnight, emotional closeness. How they look after their sexual health. The rules differ from couple to couple, and rightly so.

More important than the content of the rules, though, is how they came about. An agreement that one partner proposes and the other accepts for fear of otherwise losing them is not a real agreement — it is a capitulation with a shelf life. Nor is an agreement that can’t be changed when circumstances change. A healthy agreement has three qualities: both of you genuinely want it, both of you can reopen it for discussion at any time, and both of you know what happens if someone breaks it.

This is where boundaries come in — not as rules one person sets for the other, but as clarity about what each of you can and can’t manage. If you find it hard to say what you want, you may find Assertiveness: how to say what you want without aggression or apology helpful.

How the start of the conversation might sound

Let’s go back to the couple from the beginning. Their conversation might continue like this (composed, not a real person):

“Why now? Why at all?”
“I’m not sure. Maybe because I feel we’ve come to a standstill. It’s not that I don’t love you.”
“But to me it feels like that’s exactly what it is. That I’m not enough for you.”
“You see, that’s what I was afraid of. That’s why I kept quiet for so long.”
“I’d rather you told me. I just don’t know whether we’re talking about an open relationship or about the fact that we’ve come to a standstill.”
They are silent for a long time. “Maybe the second one first.”

This conversation doesn’t lead to a decision, and rightly so. But it does lead to an important distinction: sometimes a proposal to open the relationship is really a proposal for change — and opening up is simply the first form of that change someone has found. Once a couple can tell these apart, they can talk about what is really in question.

Questions a couple can ask themselves

Whether a couple ends up staying monogamous or not, these are questions that bring clarity to the relationship. They don’t need answering in a single evening.

Beyond these four there are other, more personal questions. What does faithfulness mean to me — is it about the body, the emotions, honesty? What did I see about love and exclusivity in my family of origin? Is there something I miss in the relationship, and could I find it within it? Can we talk about sex now, before we even mention anyone else? If that is hard, a good place to start is How to talk to your partner about sex without blame.

In relational family therapy, in which I am training, questions like these also lead us to look at how patterns from the family of origin repeat in the relationship. Someone who learned at home that love means confinement may be looking for air in the idea of openness. Someone who experienced abandonment may hear a threat in the very same idea. Both reactions are understandable — and both are worth talking about before they become a decision.

Exercise: before you talk

This is an exercise each partner does alone before you talk about the subject together. It isn’t about making a decision, but about coming into the conversation with a clearer picture of yourself.

1. Take a sheet of paper and twenty minutes on your own. At the top write: “When I think about an open relationship, I feel …” and add every emotion that comes up, including contradictory ones.
2. For each emotion, write down what it fears or what it wants. For example: “curiosity — I want something new”, “fear — that I will matter less”.
3. Write down what faithfulness means to you, in your own words, in three sentences. Not what ought to be true, but what really is true for you.
4. Write down one need you are currently missing in the relationship, regardless of the question of openness. You will find a short explanation of what a need is in the knowledge base.
5. Choose one sentence to start the conversation with — one that is about you, not your partner. For example: “I noticed that when you asked, the first thing I felt was fear.”

When you both bring your notes, the conversation doesn’t start with “yes” or “no”, but with understanding what is going on in each of you.

When opening up is not the answer

I also want to be clear about where this subject calls for caution.

As a rescue for a relationship that is falling apart. Opening a relationship doesn’t fix one in which the partners don’t talk, avoid each other or argue all the time. It brings more complexity, more conversations about sensitive subjects and more opportunities for pain. A relationship that can’t manage difficult conversations even now will struggle to bear that weight.

As a cover for infidelity. Sometimes the suggestion of an open relationship appears after infidelity has already happened — as a way of retroactively legitimising something that was hidden. Then the wound that was caused needs to be addressed first. How a relationship can be rebuilt after betrayal at all is the subject of After infidelity: can the relationship be rebuilt? In her book on infidelity, Esther Perel points out that behind many affairs lies a longing for a different version of oneself more than dissatisfaction with one’s partner — something worth knowing when thinking about openness too.

When consent isn’t free. If one partner agrees because they are afraid of otherwise being left alone, or because they are dependent in the relationship — emotionally or financially — that is not consent. If you are experiencing pressure, threats or violence in your relationship, you can call the SOS helpline for women and children who are victims of violence on 080 11 55 in Slovenia, and in an emergency 112 or the police on 113.

Against both camps. Research doesn’t show that monogamy is the only healthy form of relationship. Nor does it show that non-monogamy is more mature or more honest. Anyone who presents opening up as a sign of emotional development puts a partner who doesn’t want it in the position of someone who is “behind”. That, too, is a form of pressure. Differentiation — the ability to stay yourself while staying in the relationship — means both partners can say what they really want without having to win the other over. More on this in Differentiation: how to stay yourself and stay in the relationship.

Where couples therapy fits in

Couples therapy is not a place where the therapist tells a couple whether or not to open their relationship. It is not a place where one form of relationship is declared the right one. It is a place where both people can hear each other — even when they want different things.

In it, a couple can explore where the question comes from, what each of them hears in it and how patterns from their own stories repeat within it. And when a couple have already chosen a different form of relationship, they can talk there about jealousy, agreements and trust just as any other couple would — without judgement and without cheerleading.

What to remember

• Consensual non-monogamy is distinguished from infidelity by consent and openness, not by the number of partners.
• Research mostly shows no significant differences in satisfaction between monogamous and consensually non-monogamous relationships — but the samples have limitations.
• Jealousy doesn’t disappear in any form of relationship; the difference lies in how a couple understand it and talk about it.
• A real agreement is one you both truly want, can both reopen and both know the consequences of breaking. Agreeing out of fear is not consent.
• A question about openness is often a question about the relationship itself — and it is worth hearing before it becomes a decision.