Brad Keywell is co-founder and CEO of Uptake, an industrial A.I. startup that achieved unicorn status in its latest funding round. In a recent video interview with LinkedIn managing editor Chip Cutter, Keywell revealed that there's a very specific ritual he does every Sunday night--one that makes a big difference to his employees and also his family.

Artificial intelligence is a highly complex, cutting edge, constantly evolving technology, so you might think Keywell would spend his Sunday evenings reading up on the latest advances. But no, he spends them doing something much simpler, more profound, and to his mind, more important: He writes a weekly letter to his employees.

The weekly letters go to the 750 people who work at Uptake, as well as Keywell's family members. The Sunday Letter began as a New Year's resolution in 2016, and since then he's never missed a Sunday, not even during vacations and holidays.

Why is it so important? "It's the same reason I say that a handwritten note, if I receive it from you, means so much more than a text," he explains. "If I receive your thoughts in the form of a letter that you actually sit down--no ghostwriters allowed--write the letter in your own language and send it to me, I feel like I get to know you."

Keywell says it takes him between one and three hours to write his letter. Throughout the week, he's on the lookout for good letter subjects--such as an interesting comment heard at a conference. The letters are usually 700 to 1,000 words long, although they can sometimes run to 1,500 words, and occasionally are much shorter, after his kids complained about the length. The subjects are decidedly personal and might include things like accounts from Keywell's youth or his favorite poem. He's sharing the stories, he says, "that are coloring in my life, that are making my life fulfilling and interesting." Whatever the subject, Keywell makes sure to write about how it relates to "you the reader," and to Uptake.

But that's just how Keywell does it, he emphasizes. If you were to take this idea and use it yourself, he says, "Who says there have to be some rules for what a Sunday letter needs to be?" Different lengths, different subject matter, different formats--it's all possible. There's only one rule Keywell recommends you stick with: Write it yourself.

Employees are hungry to know who you are as a person and how that relates to the company and to them, he explains, and a Sunday letter can satisfy that hunger. "There's something about a letter that's magnificent," he says. "Even if you have self-hatred about your writing ability. Who cares if it's written perfectly? It's yours. And it's more than a text, it's more than a chat."

It's also a fulfilling activity for the person writing the letter, he says. "A weekly letter is an extraordinary way to force that activity with the discipline that a CEO probably covets. It's an expectation that's self-defined. I owe it now, it's part of what I do for everybody, and ultimately for myself."

This is why, he says, "I deeply recommend that CEOs give themselves and their employees and their personal and professional worlds the gift of their thoughts on a consistent basis through a letter." The people who work for you will learn more about you. And you may wind up learning more about yourself.