Adam Grant speaks about "Option B," his new book written with Sheryl Sandberg, at a Commonwealth Club event in San Francisco.

Adam Grant, Wharton's top professor and an organizational psychologist, researches and writes about how to improve people's lives at work. With only 30 percent of full-time workers in the U.S. "engaged" at work, according to a 2017 post from Gallup chairman and CEO Jim Clifton, Grant has his work cut out for him. "One of the questions I get more often probably than any other is: 'How do I make my work more meaningful? How do I find a sense of purpose in my job?'" Grant tells CNBC Make It. "So many of us work in jobs that are not meaningful and motivating," says Grant. "Given that we spend about a quarter of our lives at work — maybe more — it's kind of a travesty to say we're going to spend most of our waking hours doing something that we don't think matters that much. So it's not a surprise that people are searching for meaning in work." To find that meaning, Grant, co-author of "Option B" with Facebook executive Sheryl Sandberg, says the first step is to identify and organize what you are passionate about.

"You may have a hobby that you're passionate about, you may have an experience with your family that you get deep meaning from — it could be religion. "Make a list of the biggest sources of meaning in your life," says Grant, and then ask yourself a one-word question about each: Why? The top-rated professor at Wharton for seven straight years says he does this with his students, and the exchange may go something like this: Student: "I find I find exercise really meaningful." Grant: "Why?" Student: "Well, because, it's a challenge for me, and I really have to push myself." Grant: "Great. Why is that meaningful?" Student: "I value personal growth." Grant: "Ok, why?" Eventually, his students tire of the question admits Grant, but he's doing it intentionally.

"I want to get to the deeper reasons they really care about the activity, and when I ask that next question, eventually, they'll say, 'Well, it's just important to me. It's just who I am.' And at that point you've reached what psychologists would call a 'core value,'" says Grant. A core value is a one that is "intrinsically significant" to you, he explains, not because it helps you achieve something else, says Grant. "Once you know what your core values are, there are two ways to use them to make your work more meaningful," he says. One is to see if you can connect the parts of your job that don't feel meaningful to a core value, says Grant, who hosts "WorkLife with Adam Grant: A TED original podcast." "For example: Answering emails can seem trivial," Grant tells CNBC Make It. "But when I remember that it's connected to one of my core values — responsiveness — it takes on a new meaning. Instead of focusing on the boring aspects of replying, my attention shifts to the meaningful act of helping." The other trick is to find a way to work your core values into your job, says Grant. Amy Wrzesniewski and Jane Dutton have studied what they call "job crafting," and it can be helpful in bringing meaning to your job, Grant suggests.

Job crafting is "this idea of saying, 'Look, you know somebody wrote a job description for someone other than me, and I have unique interests and values and skills that I could bring to the table that would allow me to be more effective and find more meaning in my work. And so I'm going to become an active architect of my job and I'm going to change the way that I do it, or I'm going to change what I work on,'" says Grant. That does not mean advocating for doing whatever you want at work. Instead, pitch your boss a meaningful side project that will take up about 10 percent of your time at the office, says Grant. Alternatively, get a group of colleagues together for a communal activity that feels meaningful, which will also increase your sense of purpose. For example, start a book club, says Grant. "I saw that happen in multiple organizations where people said, 'You know what's really meaningful to me about my job is helping other people to learn. But I don't get to do that very often, and if I could gather a group of people who all wanted to learn together, I would feel like I'm contributing something to their our lives,'" says Grant. "Those are some some fun ways to add a little bit of extra meaning to your work." See also: This is the No. 1 trait of great leaders, says a Wharton professor who's studied thousands of executives

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