Ellen McCarthy, a wedding and relationships reporter at the Washington Post, spent years interviewing hundreds of couples about what makes relationships work and what doesn’t for the paper’s On Love column. Her book, The Real Thing, is an insiders scoop into what makes some marriages work and others..not work..and possibly end in divorce.

According to McCarthy, there seems to be two major keys to finding a marriage partner to be with for (hopefully) your entire life. They weren’t what I thought they’d be. At first I found them way too simple. But simplicity can be deceptive…

The two keys are:

1. Comfort
It turns out that so many of the spouses in successful marriages used the word ‘comfortable’ when talking about their significant other that McCarthy began to get worried when couples didn’t mention that word.
Comfortable in this case didn’t mean settling or boring. It meant that both spouses felt very much themselves in the relationship. The couple still had to work on the relationship of course, but the marriage just felt natural and they didn’t have to second guess themselves or tiptoe around one another. Both husband and wife were comfortably able to express themselves without fear. One person even said that the marriage sometimes felt like being alone while together …in the best way. They both still felt extremely free and independent while together in the relationship. This is the best kind of interdependence, I think.

2. Kindness
When asked what the most important quality a potential life partner could have, the answer was kindness, hands down. The marriages that lasted consisted of partners who were kind to one another…and kind people overall. One respondent said that her significant other was kind to everyone- kind to her, kind to himself, kind to friends, kind to dogs. Kindness is everything in a lasting marriage.
And why shouldn’t it be?

If you’re going to be with someone for life- and in this day and age that means another 60 possible years from your thirties(!)- why wouldn’t you choose someone who’s kind and who you can comfortably be yourself with?

This doesn’t mean that there aren’t butterflies, super hot moments, and great chemistry, and it doesn’t mean that everything is boring and tranquil. It just means that when looking for a life partner, kindness and comfort are great places to start…and continue.

Are you in an amazing marriage with a kind partner who you feel extremely comfortable with? Are these traits valuable to you? I know that I never had them high enough on my radar before, and they’ve recently moved to the top of my list. I don’t want to be with a person who seems great on paper, but isn’t kind. I want to be with a kind person who makes me feel comfortable and good about myself. The rest can be figured out thereafter.