The longest, healthiest marriages have these 6 defining traits

When you’re aware of your partner's joys, triggers, dreams, and worst nightmares, you’re able to interact with them in an empathetic, validating way.

Everyone who says “I do” hopes for not just a marriage but a great marriage. One that, according to Christina Eller, LMHC, a psychotherapist specializing in treating couples, is based on “a solid friendship where you're nurturing each other and where you have high regard, fondness, and admiration for one another.”

The million-dollar question is: What qualities separate an ephemeral partnership from one that can stand the test of time? And is there any way to cultivate those qualities in your own relationship? Research conducted on lifelong, happy pairings reveals five traits in those who commit to the long haul and stick with it. Below, Eller breaks down those qualities so you can look for—and foster them—in your marriage.

1. Partner knowledge

No surprise here: Partners in successful marriages genuinely know one another. When you’re aware of your partner's joys, triggers, dreams, and worst nightmares, you’re able to interact with them in an empathetic, validating way. “When we're validating, we're creating space for our partners to experience emotions and also to process their emotions without the fear of being judged or rejected,” explains Eller.

2. “Turning toward” one another

A study conducted by psychologist John Gottman of the Gottman Institute, a leader in research on marriage, recorded newlyweds' verbal and physical behaviors. Six years later, after following up with the couples, Gottman determined what traits observed in those early days of marriage translate to a long and loving partnership. He determined that couples that physically “turned toward” one another were more likely to stay in their committed relationship. Specifically, the couples who stayed married turned toward one another about 86% of the time, whereas couples that divorced only turned to one another about 33% of the time.

“When you’re crossing your arms or becoming flushed, when your heart rate is beating fast, or jaw is clenching—all of these are signs of a disaster in a relationship,” Eller says. Instead, try to angle your body toward your partner and speak calmly and gently.

This action of “turning toward” can be verbal as well. “Emotional validation is probably one of the most essential ingredients when building a relationship,” Eller says. “Validating language between two people creates empathy and creates mutual respect. And when you have those two things, you're more inclined to be magnetic towards one another.” Phrases like, “I’m hearing that you feel stressed for XYZ reason” or “That would have hurt my feelings, too.”

3. Buying into “bids” for attention

Gottman also found that couples in long-term marriages recognize when their significant others are trying to capture their attention. They answer the question “How was your day?” with specificity and respond to requests like, “Can you take out the trash?” They recognize when their partner wants affection or has a joke they want to share.

In short, they don’t split their attention between their partner and their phone. They offer their partners curiosity. Or, if they’re in the middle of something, they say, “I can’t wait to hear about this later. Maybe we can talk after XYZ?”

4. Conflict resolution

Coming back together after a fight is key for spouses who are in it for the long haul. Rather than ignoring one another or waiting for conflicts to simmer out on their own, strong partners take some time apart to think and then initiate repair.  “The ability to repair is so important,” says Eller. “If we are not vulnerable, then we are not going to be able to have an emotional connection, not only to our partner but to ourselves. Vulnerability helps with emotional connection and trust building. It helps with intimacy in our relationships, and that can make our partners feel recognized and appreciated.”

The ability to reconvene and overcome gridlocks will also offer you and your loved one a sense of shared meaning. After all, this “marriage” thing is a lifelong project that requires care from both parties.

5. Self-knowledge and self-soothing

Self-knowledge is also essential for long-term coupling. After all, if you don’t know who you are and what you value, how will communicate your needs to your partner?

“We need to be able to understand our trigger, our pasts, our childhoods, and how all of these factors can escalate the interactions with our partners,” Eller explains. “Those stories are so important for our own selves to know when we’re in a marriage.”

While your partner may help you feel better, great partnerships are made up of individuals who know how to care for themselves. Maybe you can tell when you need a day alone, a workout, or a night out with friends. Keeping up with the needs—whatever they may be for you—will help you give your marriage the energy it needs when it needs it most.

6. Acceptance of what marriage promises and what it does not

Last but certainly not least, good spouses don’t expect their marriages to be harmonious 24/7/365. “Fights are inevitable. We're human beings,” says Heller. “There's no way that people can be together for 20 to 60 years of marriage (or more) without having a conflict. However, the way we handle ourselves in conflict makes a difference.”

Remember that your marriage is a constant collaboration. It will evolve with time—as long as you keep “turning toward” each other (in all meanings of the phrase).

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This story was originally featured on Fortune.com