A strong open marriage is transparent, with specific, mutually-agreed upon ground rules. You may have other sexual partners, but you always return to your marriage, explained Greg Cason, a Los Angeles-based therapist.
"You have to make sure your marriage is something that brings both of you back home," he told HuffPost.
Below, Cason and other experts share their best advice for broaching the subject of an open marriage with your spouse.
1. Know that an open marriage takes a strong foundation.
You're starting off on the wrong foot if you're seeking solutions to your marital problems via an open marriage, Cason said.
"An open marriage is a sure-fire way to hasten the demise of a marriage that's already in a weakened state," he said. "Don’t do it if there is any question about the solidity of your relationship. This is not a remedy; it’s an adventure."
2. Bring up any and all reservations.
This isn't a decision to take lightly. You're heading for disaster if you're not on the same page about why you're opening your marriage, said Jenny Block, the author of Open: Love, Sex and Life in an Open Marriage.
"Don't even take baby steps into it until you are clearly walking on the same path," she said. "Believe me, you’ll still hit potholes -- but if you want to avoid craters, talk to one another and be completely, totally and brutally honest."
3. Ask yourself: How will I handle knowing my partner is with someone else?
Be honest with yourself about how you might feel if your spouse is with someone else -- or ends up having more sexual partners than you -- said Chris Maxwell Rose, a sex educator and the creator of the Pleasure Mechanics online courses.
"Keep in mind that in most open marriage situations, women get far more offers than men," she said. "Partners need to be prepared for this and be ready for their spouses to be with other people, whether or not they themselves are getting any action."
4. Be prepared for your partner to say "no."
When you envision the conversation you'll have with your spouse, give some thought as to what you'll do if he or she is not interested in an open relationship, said Ish Major, a psychiatrist based in New York City.
"If they give you an unwavering no, be prepared for the fallout," he said. "First, the disappointment that you would even ask. Then, the insecurity of realizing that they’re not enough for you."
To curb the likelihood of hurt feelings. Major suggests beginning and ending your conversation with this simple statement: "I love you and I'm committed to you. You’re enough for me but I'm just wondering about this."
5. Don't try to coax a "yes" out of your partner.
Wait until you're sure that your partner is equally enthusiastic about the prospect of an open marriage before pursuing it, said Tammy Nelson, a sexologist and the author of Getting the Sex You Want.
"Your partner shouldn't feel coerced or manipulated into it," she said. "If you're unsure of how to talk to your partner, schedule some counseling with a therapist who understands open marriage. Exploring a flexible, fluid and explicit monogamy agreement is the best way to make an open marriage work."
6. If you both agree to an open marriage, lay down some ground rules early on.
The best open marriages are those with clear-cut rules that are renegotiated when necessary, said Block.
"Discuss anything and everything you can think of and then wait a week and have the conversation again," she said. "Repeat until you feel safe and comfortable dipping your toes in the open marriage water."
To settle on some rules, she suggested starting with a series of questions: Can we get involved with someone apart or only as a couple? What sex acts are allowed and which are not? Are long-term relationships outside of the marriage allowed? Can additional partners be in town or only out of town?
7. Decide if you'll tell family and friends.
There will be those who don't understand your decision to open your marriage. Others will pry for more details out of prurient interest. Ultimately, Cason said, the important thing is that you both agree on who knows about your arrangement and who you tell, "It's none of your business."
"Decide who’ll know," Cason said. "Harboring secrets will cause stress and strain on the both of you and can eventually tear your relationship apart."
8. Ask yourselves: What do we want our open marriage to look like in a year?
Mapping out where you want to be in a year's time could help you avoid conflict later on, said Nelson.
"Maybe your vision of an open relationship is sharing a fun, swinging time for a couple of weekends but your partner might be imagining that the rest of your marriage will include other loving, emotionally involved partners," she said. "Be clear about your ideas and your long-term shared vision for the marriage."
9 . Be open, transparent and honest in your communication.
Communication is the cornerstone of a good relationship -- and an absolute must in an open marriage, said Stephen Betchen, a Philadelphia-based sex therapist.
"Partners must feel safe enough to express themselves at all times, be it anger, anxiety or jealousy," he said. "Good, quality communication serves to keep the primary relationship close."