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Polyamory Has Become a Little More Mainstream

One U.S. city says domestic partnerships may include multi-partner groups.

In July 2020, Somerville, Massachusetts, became the first U.S. city to extend domestic partnership rights to groups of more than two who identify as polyamorous—that is, multi-spousal. The Boston-area city now grants polyamorous groups all the rights available to married couples: shared health insurance coverage, property inheritance, and family-only hospital and nursing home visits. Somerville City Council member J.T. Scott told the New York Times he knew of at least two dozen “poly” households in the city of 80,000.

Unlike many municipalities that recognize domestic partnerships, Somerville had no such ordinance, which prevented some unmarried couples from accessing each other’s health insurance during the COVID pandemic and denied them hospital visitation. So the Somerville City Council drafted legislation recognizing domestic partners. But Scott objected to wording that defined the relationships as “entities of two persons.” The Council rewrote the ordinance to allow for more than two. It passed unanimously.

No one knows if health insurers and Somerville employers will extend spousal rights to poly groups. Court tests are expected. But it appears that the Somerville ordinance marks the first time any U.S. municipality has officially recognized—and legalized—polyamorous unions.

Less About Sex Than Negotiation

The vast majority of Americans profess monogamy—while, in secret, many have affairs and many men patronize sex workers. Meanwhile, some couples temper demands for absolute monogamy with negotiated arrangements that allow alternatives—from limited permission to play on the side (hall passes), to flings or regular couplings with other partners (sex clubs, swinging), to spousal commitments to more than one other person (polyamory).

This isn’t cheating. It’s based on mutual consent, full disclosure, diligent safe sex, and in the case of polyamory, ongoing group discussion to minimize jealousies and sort out the myriad complexities involved in maintaining polyamorous lives. Many people assume that what drives poly groupings is lust. Actually, polyamorists say their lifestyle is much less about sex than intimate conversation and negotiation.

A Long History

If you think polyamory is new, think again. In the Bible, polygamy was common. From the American Revolution through the late nineteenth century, a small minority of Americans joined frontier utopian communities, each with its own relationship rules. The Shakers insisted on celibacy. The Mormons embraced polygamy. And in 1848 in Oneida, New York, John Humphrey Noyes established a “communist” community. All property was held by the group and traditional marriage was abolished in favor of “complex marriage.” Men could invite member women to bed. Women were free to accept or decline, but the community opposed exclusivity and encouraged multiple partners. Most Oneidans maintained several simultaneous relationships. At its height, the Oneida commune numbered 300. It lasted 31 years, until 1879.

During the 20th century, poly groups continued to bubble up. In 1956 in New York City, John Peltz "Bro Jud" Presmont founded the proto-hippie commune, Kerista, that advocated “polyfidelity.” During the 1960s, Kerista communes were established in Los Angeles and San Francisco’s hippie Haight-Ashbury. Kerista dissolved in 1991.

The term “polyamorous” first appeared in print in 1990. In 1992, Jennifer L. Wesp created the Usenet newsgroup “alt.polyamory” to support poly groups.

How Many North Americans Are Poly?

No one knows, but there’s considerable interest. I searched “polyamory” and got almost 8 million results. Research into polyamory is limited—but intriguing. It’s abundantly clear that many people dream about non-monogamy that may include consensual polyamory:

  • In 2009, psychotherapist Brett Kahr collected 23,000 sexual fantasies for his book, Who’s Been Sleeping in Your Head? The Secret World of Sexual Fantasies. The most prevalent fantasy? Doing it with someone other than your main squeeze. It’s no surprise that a great deal of porn depicts threesomes, swapping, swinging, and orgies.
  • Sexologists estimate that 3 to 5 percent of America’s 60 million married couples have tried consensual non-monogamy (1.8 to 3 million couples), usually threesomes or swinging, and that 1 to 2 percent regularly play that way (600,000 to 1.2 million couples).
  • Among a representative 2,003 Canadian adults, 4 percent claimed involvement in non-monogamous relationships, some of which were poly, and 12 percent said their ideal relationship was “open.”
  • In a survey of 2,270 U.S. adults, Temple University researchers found that 4 percent reported ongoing consensual non-monogamy, including poly arrangements.
  • Based on Census samples of 8,718 American adults, Indiana University researchers found that 21 percent—one in five—reported at least one experience of consensual non-monogamy.
  • But polyamorists often remain carefully closeted. Coming out might provoke shunning by friends and families. In addition, being poly is not legally protected. It can get you fired, complicate divorce proceedings, and jeopardize child custody claims.

Poly Terminology

Some poly relationships are “V’s.” Like Biblical polygamy, they involve three people, one of whom is the “hinge” or “pivot” involved with the two others who are not romantically involved but may be friends. “Metamours” are one’s partner’s other partners. “Kitchen table polyamory” refers to group relationships where everyone feels sufficiently comfortable to chat together around the kitchen table. Folks who aspire to kitchen table polyamory hope to befriend their metamours. “Parallel” polyamory describes groups involving metamours who are not friends and may not even know one another.

Are Polyamorists Psychologically Healthy?

To my knowledge, there have been no studies of poly mental health. But several studies show that swingers are the people next door—with a few intriguing differences. Compared with monogamous couples, swingers usually:

  • Are more non-sexually affectionate with their spouses.
  • Consider their lives more exciting, and their sex more satisfying.
  • Report more marital sex and greater marital happiness.
  • Enjoy more marital communication.
  • Praise their primary partners more.
  • Express less jealousy.
  • Are no more likely than the general population to suffer anxiety, depression, and other mental health problems.
  • On standard psychological tests, usually fall within the normal range.

The consensus among researchers is that swingers are demographically, socioeconomically, and politically a snapshot of mainstream America—and psychologically healthy. I bet polyamorists are, too.

For More on Polyamory

I recommend The Ethical Slut: A Practical Guide to Polyamory, Open Relationships, and Other Adventures (3rd edition) by Janet W. Hardy.

I don’t claim to be an expert on polyamory. I hope polyamorous readers will correct any errors I may have made, and discuss the joys and challenges of being poly.


Barry, E. “A City Gives Family Rights to Multiple-Partner Unions,” New York Times, July 5, 2020.

Bergstrand, C. and J.B. Williams. “Today’s Alternative Marriage Styles: The Case of Swingers,” Electronic Journal of Human Sexuality (2000)

Fairbrother, N. et al. “Open Relationship Prevalence, Characteristics, and Correlates in a Nationally Representative Sample of Canadian Adults,” Journal of Sex Research (2019) 56:695.

Haupert, M.L. et al. ”Prevalence of Experiences with Consensual Non-Monogamous Relationships: Findings from Two National Samples of Single Americans,” Journal of Sex and Marital Therapy (2017) 43:424.

Herbenick, D. et al. “Sexual Diversity in the United States: Results from a Nationally Representative Probability Sample of Adult Women and Men,” PLoS One (2017) 12:7:e0181198.

Jenks, RT. “Swinging: A Review of the Literature,” Archives of Sexual Behavior (1998) 27:507.

Kahr, B. Who’s Been Sleeping in Your Head? The Secret World of Sexual Fantasies. Basic Books, NY, 2008

Levine, E.C. et al. “Open Relationships, Nonconsensual Non-monogamy, and Monogamy Among U.S. Adults: Findings from the 2012 National Survey of Sexual Health and Behavior,” Archives of Sexual Behavior (2018) 47:1439.