I recently posted a list How to make friends — or at least think about it more clearly. That list sets forth the “essential friendship skills.”

But knowing the essential friendship skills isn’t the same thing as being able to make friends. And friends are very important to happiness. The more I’ve studied happiness, in fact, the more convinced I’ve become that loneliness is a very common and very serious challenge to happiness. I think it’s a subject that deserves more attention.

Ancient philosophers and contemporary scientists agree: strong social ties are a key — arguably the key — to happiness. You need close, long-term relationships; you need to be able to confide in others; you need to belong; you need to get and give support. Studies show that if you have five or more friends with whom to discuss an important matter you’re far more likely to describe yourself as “very happy.”

Not only does having strong relationships make it far more likely that you take joy in life, but studies show that it also lengthens life (incredibly, even more than stopping smoking), boosts immunity, and cuts the risk of depression.

Strategies for Making Friends

But making friends can be difficult. Here are some strategies to try, if you’re eager to make friends but finding it tough:

1. Show up.

Just as Woody Allen said that “Eighty percent of success is showing up,” a big part of friendship is showing up. Whenever you have the chance to see other people, take it. Go to the party. Stop by someone’s desk. Make the effort. I’m a big believer in the power of online tools like Facebook, Twitter, and Google+ to help sustain relationships, but nothing can replace a face-to-face meeting.

Also, the mere exposure effect describes the fact that repeated exposure makes you like someone better – and makes that person like you better, too. You’re much more likely to become friends with someone if you see him or her often. I’ve seen this happen over and over in my life. I’ve become close to unlikely people, just because circumstances put us in constant contact.

2. Join a group.

Being part of a natural group, where you have common interests and are brought together automatically, is the easiest way to make friends: starting a new job, taking a class, having a baby, joining a congregation, or moving to a new neighborhood are great opportunities to join a group. If those situations aren’t an option, try to find a different group to join. Get a dog, for example. Or pursue a hobby more seriously. An added advantage to making friends through a group is that you’ll have something obvious in common with these new acquaintances, and you can strengthen your friendships to several people at once — very helpful if you don’t have a lot of free time. Which is important, because for many people, lack of time is a real obstacle to making and sustaining friendships.

3. Form a group.

If you can’t find an existing group to join, start a group based around something that interests you. My children’s literature reading groups – (yes, now I’ve helped start three of these groups) are among the top joys of my life. Studies show that each common interest between people boosts the chances of a lasting relationship, and also brings about a 2% increase in life satisfaction, but I’m confident that my kidlit groups have given me a lift in life satisfaction much higher than two percent. Movies, wine, cheese, pets, marathon-training, a language, a worthy cause…I know people in all these sorts of groups. You can start a Happiness Project group! (If you want the starter kit, to help launching a group, email me at gretchenrubin1 at gretchenrubin dot com.)

4. Say nice things about other people.

It’s a kind way to behave; also, studies show that because of the psychological phenomenon of spontaneous trait transference, people unintentionally transfer to you the traits you ascribe to other people. So if you tell Jean that Pat is arrogant, unconsciously Jean associates that quality with you. On the other hand, if you say that Pat is hilarious, you’ll be linked to that quality.

5. Set a target.

This strategy sounds very calculating, but it has really worked for me. When I enter a situation where I meet a new set of people, I set myself the goal of making three new friends. This seems artificial, but somehow, this shift makes me behave differently, it makes me more open to people, it prompts me to make the effort to say more than a perfunctory hello.

6. Make an effort to smile.

Big surprise, studies show that the amount of time you smile during a conversation has a direct effect on how friendly you’re perceived to be. In fact, people who can’t smile due to facial paralysis have trouble with relationships. I’ve been working hard on this myself lately; I’ve become more solemn over the years, or at least more distracted and tightly wound.

7. Make friends with friends-of-friends.

“Triadic closure” is the term for the fact that people tend to befriend the friends of their friends. So friends-of-friends is an excellent place to start if you’re trying to expand your circle.

8. Be aware of cultural differences.

On last week’s post, a commenter noted that now that she lived in the United States, she missed the kind of easy, drop-by-your-house friendships that she’d had in Australia. She just didn’t seem able to make those close friends. But I suspect that friendship intensity isn’t the problem, just cultural practice. At least in Kansas City and New York City, the places I know best, even a very close friend wouldn’t be likely to drop by your house unannounced — no matter how those crazy kids behaved on the TV show Friends. So try to be aware of how friendship signals may be different in different places.

What other strategies have you used to help build friendship? And what challenges have you faced? The ones I hear the most are 1) lack of time and 2) new place with no network to draw upon. What about you?

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