Your haircut looks great. Your speech was so moving. You are a really good friend; I can’t tell you how great it was to talk last week when I was upset.

Compliments make us feel good — both giving and receiving them.

Feeling valued and appreciated are basic human needs, explains Marcia Naomi Berger, a licensed clinical social worker and psychotherapist in San Rafael, California, and author of "Marriage Meetings for Lasting Love: 30 Minutes a Week to the Relationship You've Always Wanted".

Appreciation is also foundational in relationships, both those with our partners and spouses and with our friends, Berger adds. It’s part of what makes us want to cooperate and collaborate with those around us. And if you come to a challenge, knowing that you’re appreciated helps you want to work through and overcome that challenge.

Compliments help us communicate that appreciation we feel toward one another. “I would define a compliment as any sort of sincere appreciation of a trait in someone or a behavior or an appearance,” Berger says.

And that makes us feel good. Scientists have found that being paid a compliment actually lights up the same parts of your brain that get activated when you get paid a monetary award. Other research (from the same group of researchers) suggests compliments and praise may help us when it comes to learning new motor skills and behaviors.

Being in the habit of giving compliments helps us notice and appreciate what’s good and what we like in those around us.

Compliments also help us like one another, Berger adds. “Behaviors that get rewarded are likely to be repeated. So, if you tell someone how much you like how he smiled when you greeted each other, he’s likely to smile again on seeing you.”

Paying someone a compliment can also be a good conversation starter — or a good way to get over an awkward bump in a conversation — whether it’s a conversation with someone you know or have just met.

In this way and others it’s not just the receiver who walks away better off. Compliments benefit the giver, too. Being in the habit of giving compliments helps us notice and appreciate what’s good and what we like in those around us. “So being complimentary helps us create an optimistic, happier outlook,” Berger says.

What you should know about how to give good compliments

Not all compliments land the same. Here’s how to get better at them.

1. Compliments should be sincere

It might seem harmless to tell someone that their shoes are pretty, even though you actually think they’re hideous. But the vast majority of the time, the genuine compliment is going to go farther than the insincere one, Berger says.

“So much of what we say gets communicated by what your voice tone is imply and your body language,” she says. And most of us have a sixth sense when it comes to sniffing out when what someone is saying insincere. Everybody has qualities that deserve complimenting, Berger says. Pay attention and recognize them.

2. Pay attention

Key to giving compliments (and being good at giving compliments) is paying attention to the people around you and paying attention to the details. “Notice what you like or appreciate about the person,” Berger says.

3. Be specific

The best compliments are specific. They refer to character traits, behaviors, or appearance, Berger says. (Yes, we all tend to like to know that we’re viewed as attractive, she says.) Hearing that someone thinks you’re smart or kind or pretty is nice to hear, but those compliments apply to a lot of people. Calling out something specific shows the other person you’re interested and paying attention.

Rather than just telling someone they look nice, tell that person: “You look so handsome in that blue shirt you’re wearing. It matches your eyes.”

4. When it comes to giving compliments, make it rain

Ideally we’re giving and receiving compliments everyday in our close relationships, Berger says. It’s really easy to take one another for granted or only make a point of mentioning the negative things that need solutions. So making a concerted effort to notice all the good things about your partner (or family member or friend) is important.

If you get in the habit of giving compliments frequently, you’ll get in the habit of noticing what’s going well frequently, too, she says. And that can help strengthen any relationship.

5. …unless the praise is making the other person uncomfortable (try this instead)

For people with low self-esteem, there’s actually some research to suggest that compliments do not tend to be well-accepted, explains Joanne Wood, Professor of Psychology at University of Waterloo, who researches the topic. “This difficulty seems likely to stem from their resistance to information that contradicts their world view — people appear to be highly motivated to hold on to their self-views, even if they are negative.”

Subsequent work from Wood’s group suggests that showing interest in the other person when they react this way may work better when it comes to strengthening relationships (rather than exchanging compliments), she says.

6. Receive compliments with grace

Other times people feel uncomfortable receiving compliments because they were taught (or might think) that accepting them equates to bragging, Berger says. But it’s not. Compliments are about communicating with those around you what you appreciate and what’s working.

Learning how to graciously accept compliments is just as important as learning how to give them, Berger says. After all, denying a compliment is another way of telling someone that they’re wrong or that their opinion or perspective is wrong (which is kind of rude if you think about it). “It’s like refusing to accept a gift from someone,” Berger says.

When in doubt, a simple “thank you” works.

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