What Is an Open Marriage?

Open Marriages Require Trust and Communication

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The term "open marriage" is sometimes called "polyamorous marriage." In an open marriage, partners are legally married to one another and describe their marriage as their primary relationship. Also, the partners agree that they are comfortable with some level of non-exclusivity. In many cases, one or both partners date or have sex with other partners regularly.


The 1972 book, Open Marriage, is often considered the source for the term open marriage. The book was on the best-seller list for 40 weeks and has sold more than 35 million copies around the world. The book itself was a relatively tame marriage manual, but approximately 20 pages were dedicated to the idea that extra-marital sexual relationships can be healthy for a marriage.

While George and Nena O'Neill only briefly mentioned extramarital sex in marriage, their book was an important factor in the sexual revolution of the 1970s.

How Open Marriage Differs from "Fooling Around"

The most important elements of an open marriage are communication and trust. When one partner is having an affair outside of the marriage, their spouse has no knowledge of or control over what's going on. In an open marriage, partners discuss extramarital relations with the understanding that any decisions will be made together. Also, partners in an open marriage must be open to making changes in their extra-marital relationships if needed: the spouse always come first.

What Open Marriage Is and Is Not

It is important to understand the parameters and limitations of open marriage. Specifically, open marriage:

  • Is a traditional, legal union between two consenting adult partners;
  • Is not a polygamous marriage such as those approved by some Mormon communities;
  • Involves active, positive communication between the marriage partners (secret sexual adventures are not part of an open marriage);
  • May or may not involve one night stands, ongoing extramarital relationships, or other types of sexual relations;
  • Is unique for every couple.

Examples of Open Marriage

Monique Angela Hicks (Mo'Nique) is a comedienne in an open marriage.

Here is what she says about the relationship:

Mo'Nique about open marriage: "Open means, you know what, let me tell you my every secret, my fantasies, my thoughts, so that way, there are no surprises ... I have not had sex outside of my marriage with Sidney. Could I have sex outside of my marriage with Sidney? Yes. Could Sid have sex outside of his marriage with me? Yes. That's not a deal-breaker."

Source: Lauren Sher. "Mo'Nique on Sex Outside Marriage: 'That's Not a Deal-Breaker.'" ABCNews.go.com. 3/04/2010.

Actors Will Smith and Jada Pinkett-Smith also have an open marriage. Here is their description of how it works:

In our marriage vows, we didn't say 'forsaking all others.' The vow that we made was that you will never hear that I did something after the fact...If it came down to it, then one spouse can say to the other, 'Look, I need to have sex with somebody. I'm not going to if you don't approve of it - but please approve of it.'"

Source: The Guardian. 2/09/2005