By Laura Snyder

In a society that seems to insist we find "The One," that single partner who can fulfill all our emotional and sexual needs, people get deeply suspicious about open relationships.

"That can never work."

"I've never known anyone who could do that."

But people can do it and it can work. But not without a little effort from both partners to lay down the ground rules. Your own policies may be different, but the most common guidelines include:

You're Both Interested

Open relationships tend to work best with people who have strong hearts and a good relationship track record (i.e. if you're still bruised about an ex who cheated, you are less likely to be cool with a partner who sleeps around). Too often, however, one person in the relationship suggests seeing other people - perhaps even because they already have someone in mind - and the other person goes along with it to appear cool, or open, or just to avoid conflict. If you're not both totally on board with this arrangement, it will not end well.

If You're Not Communicating, You're Just Cheating

The difference between being in an open relationship and just being a slimy cheater is that your primary partner knows about your little side project before the clothes come off (and is okay with it). Ideally, you'll start talking about seeing other people long before it actually happens and you'll both be in board with how it will go down (for example, are you allowed to bring your new friend home to the bed your share? Are you allowed to pursue side-relationships or only one-night-stands?).

Keep Things Friendly

Seems like it might be awkward, but many couples in open relationships recommend that all parties meet each other. A friendly meet-up can help keep everyone on the same page about the situation - and we shouldn't have to tell you that sometimes very interesting things can happen when three sexually-progressive people knock back a few glasses of wine together.

Always, Always Be Safe

Arrangements may vary among couples - some prefer not to know anything at all about what their primary partner is doing on the side - but even among couples with "no rules," there's always this one: practice safe sex every single time. It's not just about keeping yourself healthy; it's also your (very important) responsibility to keep your primary partner safe from your dalliances.