Nine chief executives shared the books they’ve used to educate themselves.

Article by Beck Bamberger** | Fast Company

Leaders are readers. It’s a mantra many of us heard growing up, and it turns out it’s true. In particular, research suggests that leaders read to gain a competitive edge. Author Steve Siebold dedicated 30 years to studying 1,200 of the world’s richest, most accomplished people and found that they all have an “extensive library of books they’ve used to educate themselves on how to become more successful.”

Anytime is the perfect time to curl up with a good read, so we asked nine CEOs for the books they’re interested in giving to other—and getting:

If you want your company to endure, Helmer contends that it must first create power. Helmer describes how in this book, which earns high marks from Jonathan Wasserstrum, cofounder and CEO of real estate technology company SquareFoot. “This isn’t your average coffee table business book. It’s ten times better,” he says. “It may scare some folks with the equations, but those can be skipped without worry.”

This book sheds light on how AI could empower physicians to revolutionize patient care. That includes the emerging role of virtual medical assistants, which is of particular interest to Susan Bratton, founder and CEO of Savor Health.

The company uses an intelligent chatbot called Ina to give cancer patients personalized nutrition interventions. “Ina can’t be an un-emotive robot bot that only delivers facts and answers,” she says. “We are dealing with very sick, frightened people. So, in addition to providing with the most clinically appropriate advice, we must also deliver it in a compassionate, empathetic, and understanding manner.”

Raising capital for your company can be daunting. This book can help though, says Cody Barbo, founder and CEO of Trust & Will, an online service that simplifies estate planning.

“[This book] does an exceptional job of outlining the ‘secrets’ of fundraising from one of the best firms in Silicon Valley,” he says. “Being able to look at fundraising through the lens of a VC allows you to be highly tactical in your approach.”

He says that the insights have already proven successful in building two venture-backed startups over the past six years. “I loved picking up a few new skills and insights for our next venture round,” says Barbo.

The nexus between physics and entrepreneurship may not be obvious, but it’s there. At least according to Dmitry Shevelenko, cofounder and CEO of Tortoise, which delivers e-scooters to riders.

“Entrepreneurship is an exercise in taming the unknown, and Deustch’s work will leave you optimistic that, as long as the laws of physics allow it, any problem you encounter can be solved with sufficient knowledge,” he says.

In fact, this book contends that excelling as a CEO is like many things: it takes ongoing training. Owning that is a good thing, Waxman says. “It’s exciting that we’re recognizing how hard it is to be founder and that it’s okay—even necessary—to get help,” he says. “I can’t wait to read this book and bring back some lessons to my own coach.”“In the past few years, every founder I know has gotten an executive coach—myself included,” says Michael Waxman, cofounder and CEO of dog food brand Sundays.

What do some of the most successful CEOs have in common? And what can we learn from that? This book studies eight CEOs who drove their companies to outperform the market.

“I first read this book as I was starting my company, and it helped me develop my own blueprint for [being] a CEO,” says Jeff Cripe, founder and CEO of Cargo, which delivers in-car goods and services for the ride-share economy. “I read it again recently, and it was a good to do some self-evaluation and recalibrate that blueprint for our next few years of growth.”

“This is a revolutionary book and a must-read for everyone,” says Eric Marcotulli, founder and CEO of Elysium Health, a supplement line based on emerging science in genomics and longevity.  He says that he found the research on cognitive bias, or our patterns of deviating from rational judgement, especially useful. “Understanding cognitive bias and its influence on our thought processes is central to critical thinking, which is an important skill for any founder.”

Picking just one book was a challenge for Ashley Sumner, cofounder and CEO of Quilt, a community platform for women to open their homes to other women for coworking or group forums. But ultimately, she says this one tops her list because it reminds her to double down when her gut tells her to go against the grain.

“As an entrepreneur and CEO with investors and shareholders, it can be very easy to get pushed into thinking like everyone else. But the whole reason I’m where I’m at today is because I don’t,” she says. “This book did a beautiful job of reinspiring the original in me, the unconventional thinker, while debunking some myths around what is necessary to become an original.”

“Ben Horowitz is a Silicon Valley venture capitalist and thought leader who I’ve followed and respected for a long time,” says Julie Roth Novack, cofounder and CEO of event-planning platform Party Slate.

She especially enjoys the author’s nontraditional approach to business advice and says his latest work is no exception. “In his new book, Horowitz takes another unique perspective, this time using nonbusiness, historical figures and their experiences to suggest how to build a strong company culture,” she says. “As a startup CEO of a fast-growing company, a strong culture is key to scaling and retaining top talent.”

** Beck Bamberger founded BAM Communications in 2008 and writes regularly for Forbes, Inc., and HuffPost about entrepreneurship, public relations, and culture.