Robert Emmons, perhaps the world’s leading scientific expert on gratitude, argues that gratitude has two key components, which he describes in a Greater Good essay, “Why Gratitude Is Good.”

“First,” he writes, “it’s an affirmation of goodness. We affirm that there are good things in the world, gifts and benefits we’ve received.”

In the second part of gratitude, he explains, “we recognize that the sources of this goodness are outside of ourselves. … We acknowledge that other people—or even higher powers, if you’re of a spiritual mindset—gave us many gifts, big and small, to help us achieve the goodness in our lives.”

Emmons and other researchers see the social dimension as being especially important to gratitude. “I see it as a relationship-strengthening emotion,“ writes Emmons, “because it requires us to see how we’ve been supported and affirmed by other people.”

Because gratitude encourages us not only to appreciate gifts but to repay them (or pay them forward), the sociologist Georg Simmel called it “the moral memory of mankind.”

For more: Learn about the GGSC’s Expanding the Science and Practice of Gratitude project, co-directed by Emmons.

Why Practice Gratitude?

Over the past decade, hundreds of studies have documented the social, physical, and psychological benefits of gratitude. The research suggests these benefits are available to most anyone who practices gratitude, even in the midst of adversity, such as elderly people confronting death, women with breast cancer, and people coping with a chronic muscular disease. Here are some of the top research-based reasons for practicing gratitude.

Gratitude brings us happiness: Through research by Emmons, happiness expert Sonja Lyubomirsky, and many other scientists, practicing gratitude has proven to be one of the most reliable methods for increasing happiness and life satisfaction; it also boosts feelings of optimism, joy, pleasure, enthusiasm, and other positive emotions.

On the flip side, gratitude also reduces anxiety and depression.

Gratitude is good for our bodies: Studies by Emmons and his colleague Michael McCullough suggest gratitude strengthens the immune system, lowers blood pressure, reduces symptoms of illness, and makes us less bothered by aches and pains. It also encourages us to exercise more and take better care of our health.

Grateful people sleep better: They get more hours of sleep each night, spend less time awake before falling asleep, and feel more refreshed upon awakening. If you want to sleep more soundly, count blessings, not sheep.

Gratitude makes us more resilient: It has been found to help people recover from traumatic events, including Vietnam War veterans with PTSD.

Gratitude strengthens relationships: It makes us feel closer and more committed to friends and romantic partners. When partners feel and express gratitude for each other, they each become more satisfied with their relationship. Gratitude may also encourage a more equitable division of labor between partners.

Gratitude promotes forgiveness—even between ex-spouses after a divorce.

Gratitude makes us “pay it forward”: Grateful people are more helpful, altruistic, and compassionate.

Gratitude is good for kids: When 10-19 year olds practice gratitude, they report greater life satisfaction and more positive emotion, and they feel more connected to their community.

Gratitude is good for schools: Studies suggest it makes students feel better about their school; it also makes teachers feel more satisfied and accomplished, and less emotionally exhausted, possibly reducing teacher burnout.

For More: Read Emmons’ essay about “Why Gratitude is Good.”

How to Cultivate Gratitude?

Are you a natural pessimist? Take heart: The benefits of gratitude aren’t only available to people with a naturally grateful disposition. Instead, feeling grateful is a skill we can develop with practice, reaping its rewards along the way. Here are some of the most effective ways to cultivate gratitude, according to research.

Keep a gratitude journal, recording three to five things for which you’re grateful every day or week. Because some evidence suggests that how we keep a gratitude journal—for instance, how often we write in it—can influence its impact, the GGSC’s Jason Marsh offers these research-based tips for gratitude journaling. Apply these tips through the GGSC’s new and easy-to-use online gratitude journal, Thnx4.org.

Write a “gratitude letter” to an important person in your life whom you’ve never properly thanked. Research suggests gratitude letters provide strong and long-lasting happiness boosts, especially when they’re delivered in person. When participants in her studies write gratitude letters, Sonja Lyubomirsky provides them with these instructions.

Savor the good in your life—don’t just gloss over the beauty and pleasures that come your way. Loyola University psychologist Fred Bryant has identified 10 ways to practice savoring; GGSC advisory board member Rick Hanson has developed his own method for savoring positive emotions and experiences, which he calls “taking in the good.“

Focus on intentions: When you receive a gift, or when something good happens to you in general, consider how someone tried on purpose to bring that goodness into your life, even at a cost to themselves. Research suggests this goes a long way toward cultivating “an attitude of gratitude,“ among children and adults alike.

Teach gratitude to children: Researchers Jeffrey Froh, Katherine Henderson, and colleagues have developed a gratitude curriculum for kids, based on Froh’s work studying gratitude in schools; results suggest it can boost gratitude and happiness for five months. The gratitude journal and gratitude letter exercises have also proven effective with kids.

Recognize the positive: The GGSC’s Christine Carter asks her daughters about three good things that happen to them each day—a way to help them appreciate the gifts big and small that come their way.

Get metaphysical: Research suggests that thinking hard about our own mortality makes us more grateful for life; another study found that praying more often increases gratitude.

For more: Check out Emmons’ 10 Ways to Become More Grateful and journalist Catherine Price’s entertaining article about how she tested gratitude practices on herself. And don’t forget to start counting your blessings through the GGSC’s online gratitude journal, Thnx4!

How Grateful Are You?

Find out by taking the GGSC’s gratitude quiz. You can also:

Download the six-item Gratitude Questionnaire developed by Emmons, McCullough, and their colleague Jo-Ann Tsang.

Try the Gratitude, Resentment and Appreciation Test (GRAT), developed by researcher Phil Watkins.