What Polyamorous Couples Do Every Day That Monogamy Researchers Never Thought to Study

Every relationship has a maintenance layer beneath it — the daily negotiations, disclosures, boundary-checks, and small repairs that keep it from degrading. Monogamy researchers have spent decades cataloguing that layer. The equivalent infrastructure of consensual non-monogamy, the practices people in open relationships, polyamorous arrangements, and swinging situations actually use to hold things together, has been remarkably under-examined. It turns out that the people living it have been doing the work anyway, without much help from science.

A new paper published in a peer-reviewed journal has tried to close that gap by developing the Multiple Relationships Maintenance Scale^[2] (MRMS), the first instrument designed specifically to document and validate the practices by which people in consensually non-monogamous (CNM) relationships manage the additional complexity of multi-partnering. CNM is the umbrella category for relationship structures — polyamory, open relationships, swinging — in which all parties have consented to romantic or sexual connections with more than one person. Estimates put at least 5% of the North American population in some form of CNM arrangement at any given time^[3], a figure large enough that the field's almost complete silence on how these relationships are actually maintained is striking.

What the researchers found, and what the MRMS is built around, is that CNM practitioners have not been waiting for academia to catch up. They have built their own operating procedures. Nine of them, specifically.

What Relationship Maintenance Actually Looks Like at Scale

The researchers identified nine distinct practices through which people in CNM relationships try to prevent or resolve the conflicts that multi-partnering introduces. The practices share a common logic: rather than ignoring, sabotaging, or concealing a partner's connections to others, CNM practitioners disclose those interactions and actively work with their partners to address the challenges that arise. This sounds almost clinical when written out, but it represents a meaningful behavioral difference from what research on infidelity describes. Cheating, by definition, removes the maintenance layer. The affair partner becomes a source of conflict the relationship cannot process because it does not know the conflict exists. CNM frameworks, at least in theory, keep the maintenance layer intact by making the multi-partnering visible and subject to joint negotiation. As the piece on what polyamory gets wrong about jealousy has previously explored, the emotional challenge is not disclosure itself — it is what the disclosure surfaces.

“Rather than ignoring, sabotaging, or keeping secret a partner's extra-pair relationships, people who practice CNM disclose these interactions and work together to address the challenges multiple relationships introduce.”

The scale was developed and validated internationally, which matters because CNM norms and terminology vary considerably across national contexts. What counts as a primary partner, what agreements are assumed versus negotiated, what level of disclosure is expected — these are not universal defaults. By testing across populations, the researchers were able to identify practices that appear common across different CNM configurations, rather than those specific to any one cultural context or community.

The Hierarchy Question

One of the more structurally interesting findings embedded in the paper concerns the difference between primary and secondary partnerships. Prior research, including work by Balzarini and colleagues^[1], has found that primary partnerships in CNM arrangements tend to entail more commitment than secondary ones — and that polyamorous individuals often report greater commitment to one partner than another. The MRMS research builds on this by noting that pseudo-primary and primary partners are more comparable to monogamous partners than they are to secondary partners in terms of relationship quality and the expectations placed on the relationship.

That finding complicates a certain idealized picture of CNM as inherently flat and egalitarian. Many people practicing polyamory or open relationships do maintain tiered structures, even when they resist that language. The MRMS is designed to track those distinctions, measuring not just whether maintenance practices occur, but how they differ across the varying levels of a person's relational network. Compersion — the feeling of joy at a partner's joy with another — is often cited as the emotional goal, but the structural reality is that hierarchy persists, and the maintenance work required varies significantly depending on where in the hierarchy a relationship falls.

What the Tool Is Actually Measuring

Beyond cataloguing practices, the MRMS examines how engagement in those practices predicts relationship quality. The researchers measured outcomes including satisfaction, commitment, interdependence, and self-reported infidelity — defined here as how often extra-pair interactions feel to the individual as though they violate the existing relationship's agreements. That last metric is important. In CNM research, agreement violation, rather than extra-pair sex itself, is the operative definition of infidelity, which shifts the analytical frame considerably. The question is not whether someone is sleeping with others. The question is whether they are doing so within the terms all parties actually agreed to.

That framing treats relationship agreements as a kind of contract, and violations of those agreements as the relevant harm — not the external relationship itself. This is methodologically useful because it allows researchers to study CNM without importing the normative assumptions baked into most relationship science, which, as the MRMS paper notes, tends to take monogamy as the default and measures everything else against it. Theoretical frameworks like interdependence theory and the investment model were largely developed with monogamous relationships in mind. The MRMS is an attempt to build measurement tools that actually fit the phenomenon being studied rather than stretching an ill-fitting template over it.

The Stigma Gap

One reason robust CNM research has been slow to develop is that CNM stigma is still substantial. Despite growing public interest in non-monogamy — both academic and cultural — many practitioners still experience significant minority stress. The gap between the lived reality of millions of people and the scientific infrastructure to study that reality is not neutral. When a relationship form goes unmeasured, its practitioners are also unsupported. Clinicians lack validated tools. Courts lack conceptual frameworks. And the people inside these relationships lack the externally validated vocabulary to name what is working or not working for them.

The MRMS is a step toward closing that gap, but it is also, by its own account, a first step. The paper acknowledges that CNM practitioners have developed many strategies to manage multi-partnering challenges — and that some of these might work better than others. The scale is designed to begin answering that question empirically: which practices actually predict better outcomes, under what relational configurations, and for which partners in a network. That work is ongoing. What the paper provides is a measurement framework, not the answers themselves.

What it also provides, more quietly, is a record of something that has been happening without documentation for a long time. People in CNM relationships have been maintaining those relationships — managing complexity, disclosing discomfort, negotiating agreements, repairing ruptures — without much institutional support and without a scientific literature that took their arrangements seriously as objects of study. The nine practices the MRMS codifies did not emerge from a study. They emerged from people figuring out how to love more than one person at once without losing the ones they already had. The researchers are only now building the tools to measure what was already there.

References

1. Comparing Relationship Quality Across Different Types of Romantic Partners in Polyamorous and Monogamous Relationships (pubmed.ncbi.nlm.nih.gov)
   Establishes prior research finding that primary partnerships in CNM arrangements show more commitment than secondary ones.
2. How Do People Maintain Consensual Non-Monogamy? An International Development and Validation of the Multiple Relationships Maintenance Scale (pmc.ncbi.nlm.nih.gov)
   Introduces the Multiple Relationships Maintenance Scale, the first instrument designed to document and validate practices by which people in consensually non-monogamous relationships manage multi-partnering complexity.
3. What do we know about consensual non-monogamy? (sciencedirect.com)
   Provides the epidemiological estimate that at least 5% of North American population practices consensual non-monogamy.