Skip to main content

Verified by Psychology Today


How Complicated Breakups Shape Future Romance

Research on "mate poaching" reveals key implications for future relationships.

Mr. Robinson: I was just telling Ben here he ought to sow a few wild oats. Have a good time while he can. You think that's sound advice?

Mrs. Robinson: Yes, I do. —The Graduate, 1967

We are endlessly fascinated with infidelity in romantic relationships: why people cheat, how to predict who will cheat, how to know if your partner is cheating on you, and what to do about it. Related to infidelity is what researchers call “mate poaching,” described by Belu and O’Sullivan in their recent study (2018), adapted from earlier work, as “when someone forms (or attempts to form) a romantic and/or sexual relationship with someone who they know is already in an exclusive relationship.”

Skitter Photo, StockSnap IO, Creative Commons CC0
Source: Skitter Photo, StockSnap IO, Creative Commons CC0

Evolved to poach?

When it comes to considering long-term commitment in relationships, researchers apply two main models — investment theory and evolutionary theory. According to investment theory, if you put time and energy into a relationship — if you share finances, children, and a life together — you are more likely to want to keep that relationship going than if there isn’t much at stake, even if you aren’t feeling satisfied with the relationship and/or your partner. According to evolutionary theory, we are driven to find the best partner we can, so if someone who seems better than our current partner comes along, we may be tempted to defect and try to get that new person as our mate. In the animal kingdom, some animals, such as the cute prairie vole (studied for its evolved lifelong pair-bonding), mate for life — while others opt essentially for the one-night stand, a strategy known as "hit-and-run" mating.

Generally, if the investment is low, and the partner is not deemed satisfactory, there is little reason to remain in the relationship. If investment is high, in some cases people will find a way to try to have their cake and eat it too by continuing a long-term, committed relationship while breaking the agreement for exclusivity; they will either engage in outright infidelity, offer tacit permissiveness of having outside partners, or, more rarely, explicitly negotiate an open relationship.

In reviewing the existing work, Belu and O’Sullivan report one prior study of mate poaching that looks at relationships involving exclusively people under the age of 25 (Foster et al., 2014). That study showed that poachers tend to have a greater number of sex partners (both serious and casual), more dating partners, and less inhibited attitudes about sexuality. However, this early work did not investigate other important factors, including relationship quality, sexual satisfaction, trust, infidelity, and related concepts. Discussing prior work from a large survey (Schmitt & ISDP, 2004), the authors identified the basic features of poaching: Poaching happened in both short- and long-term relationships; most survey respondents (about 75 percent) reported at least one mate-poaching attempt during both short- and long-term relationships, and, in about half of the relationships, mate poaching led to a partner leaving the relationship for another.

The current study

From a research perspective, mate poaching is “infidelity plus.” Yet there has been little research on how mate poaching plays out in the new relationships formed after infidelity. To address these questions, the authors of the current study recruited 675 people to complete a comprehensive set of surveys about mate poaching, relationship qualities, and other relevant considerations. The participants were between the ages of 25 and 40 (reflecting more generalizable and relatable results for contemporary adults than the Foster study), with 55 percent being women. The group surveyed in this study was 72 percent White, 7.4 percent Black, 5.7 percent Hispanic, 5.7 percent South Asian, 2.2 percent Indigenous, and 6.8 percent other. Participants were only included if they were currently in a relationship. The goal of the research was to determine what (if any) differences there are between poached and non-poached relationships.

Via a survey, researchers initially asked, “Are you currently in a relationship that started while you were already in a relationship with someone else?” and “Was your current partner in a romantic relationship with someone else when your relationship with them started?” This was intended to determine if the current relationship involved poaching, and if so, who the poacher was. Formal measures included relationship history, infidelity, mate poaching, relationship commitment, relationship satisfaction, sexual satisfaction, trust, and jealousy.

Across the group, 13 percent of respondents self-identified as poachers, 23 percent identified as having been poached out of their last relationship, 6.5 percent indicated they had been co-poached (involving situations in which both partners had been in relationships prior to the poaching), and 57 percent reported they had not been in a relationship when they met their current partner. The majority (95 percent) said they were currently in a relationship or dating exclusively and not dating multiple people. On average, relationships were about 5 ½ years long, and over a quarter of survey respondents indicated that they had been unfaithful in the current relationship.

Guryanov Andrey/Shutterstock
Source: Guryanov Andrey/Shutterstock

What did we learn?

Given these basic statistics, what associations were found connecting poaching status with relationship measures, sexual satisfaction, trust, and jealousy?

First, where poaching is involved, relationship commitment is significantly decreased. In addition, for poachers, poached, and co-poachers alike, relationship satisfaction and trust are also significantly lower, and jealousy higher. Notably, sexual satisfaction was not different between poaching and non-poaching relationships.

For preventing infidelity, pay extra attention to your relationship patterns (dynamics) if you are in a relationship that has involved poaching, because infidelity is much higher if poaching is part of the picture. Two-thirds of relationships involving infidelity included poaching, compared with only 34 percent of relationships without any poaching — a statistically significant finding. In addition, only 16 percent of non-poached people reported infidelity in their current relationships. The takeaway for many: If you want to avoid being cheated on and/or avoid cheating on intimate others, stay with people who begin and end romantic relationships “cleanly,” without hazy breakups and a habit of finding the next partner before leaving their last relationship.

In co-poaching relationships — in which both partners left a committed relationship to start a new one without breaking off the first relationship — individuals reported levels of relationship commitment, trust, and jealousy similar to those of both their poacher and poaching peers. Notably however, co-poachers reported higher levels of relationship and sexual satisfaction compared with those coming from relationships with only one person involved with poaching. Rates of infidelity were 29 percent in the co-poacher group, lower than the 44 percent in the poacher or poached group, but not statistically significant. Taken together, these findings suggest that co-poached relationships are qualitatively different from relationships with unilateral poaching. It may be that when both partners leave their previous relationships to be with someone else, there is greater compatibility in their match. Yet while they may be happier with one another, the history of poaching still leads to greater levels of wariness, mistrust, and ultimately infidelity. After all, the best predictor of cheating is a prior history of infidelity.

Fine-tuning relationship satisfaction

For those navigating the murky, hazardous, and often joyful waters of relationships and dating, examining the factors contributing to mate poaching is both useful and informative when considering future behavior. If we poached our current mate, for example, it is worth thinking about in regard to our ability to be present in the relationship: Will we be on the lookout for greener pastures? If we decide to move on from our current relationship, will we repeat the history of infidelity or break up more compassionately? If we allow ourselves to be poached out of our current relationship, is that because there were issues we weren’t discussing? Can we learn going forward to address our concerns more directly, saving a lot of heartache and guilt, defensiveness and conflict? And if we are co-poachers, can we acknowledge the risks to the stability and integrity of the current relationship we may be facing, so that we can limit jealousy, build trust, and continue to enjoy a healthy, satisfying relationship?

Particularly in an age when people are living longer and experiencing changes over their lifespan which may lead them to seek different partners at different stages of life, future research on mate poaching will be important in deepening our understanding of how relationships evolve and grow. Understanding phenomena like mate poaching is essential to moving into 21st-century relatedness, as traditional dyadic relationships become less normative, and people question monogamy and experiment with new relationship forms, and sexual and gender roles shift and evolve with culture. In particular, understanding co-poaching will be important to tease apart those factors which contribute to greater satisfaction, while mitigating the effects of mistrust and jealousy in order to get a better idea of how to best enjoy a series of committed relationships over time without leaving behind a wake of destruction if and when we decide to move on.

Please send questions, topics or themes you'd like me to try and address in future blogs, via my PT bio page.


Belu CF and ’Sullivan LF. Why Find My Own When I Can Take Yours? The Quality of Relationships That Arise From
Successful Mate Poaching, Journal of Relationships Research, April 2018, Volume 9, e6, 1–10, epub ahead of print.

Foster, J.D., Jonason, P.K., Shrira, I., Campbell, W.K., Shiverdecker, L.K., & Varner, S.C. (2014). What do
you get when you make somebody else’s partner your own? An analysis of relationships formed via mate
poaching. Journal of Research in Personality, 52, 78–90.

Schmitt, D.P., & International Sexuality Description Project (ISDP). (2004). Patterns and universals of mate poaching
across 53 nations: The effects of sex, culture, and personality on romantically attracting another person’s partner.
Journal of Personality and Social Psychology, 86, 560–584.