Expressing gratitude may seem like just a matter of good manners, but taking the time to acknowledge our own blessings—big or small, and even in moments of hardship—is actually a powerful tool for improving our well-being. So powerful, in fact, that scientists and interfaith scholars alike agree that it may be the secret key to reaching that state of being that can feel all too mythical in the modern age: happiness. As Brother David Steindl-Rast, a monk, summed it up in a 2013 TED Talk, “It’s gratefulness that makes us happy.” Read on for more about how to cultivate gratitude—and ultimately achieve a state of bliss. (You can thank us later.)