Bill Gates met Warren Buffett for the first time in 1991, and one of his first questions was which business book Buffett recommended most highly.

Buffett had the answer ready, and Gates apparently took it to heart, since 23 years later he wrote about it–“The Best Business Book I’ve Ever Read”–on his blog.

What is this masterpiece?

It’s called Business Adventures, by John Brooks.

Brooks was a staff writer for The New Yorker  for more than 30 years, and he pulled items originally from the magazine for the book.

Almost like a mini-MBA (in that business school programs heavily favor case studies), Business Adventures comprises 12 stories about well-known companies (“Twelve classic tales from the worlds of Wall Street and the modern American corporation”).

Part of what’s fascinating about the (lasting) recommendations of this book is that it was published so long ago–in 1969.

As Gates states on his blog, “in 1966, when Brooks profiled Xerox, the company’s top-of-the-line copier weighed 650 pounds, cost $27,500, required a full-time operator, and came with a fire extinguisher because of its tendency to overheat. A lot has changed since then.”

It certainly has.

What hasn’t changed are the fundamental principles outlined in the book, which is likely why it has gone on to inspire greats like Gates and Buffett.

The most fundamental of those?

People matter.

Who is leading and why is critical to a business’s success. Are they good listeners? Are they willing to take risks? Do they know how to inspire their teams? Are they able to take criticism and learn to surf the waves of change, rather than resisting them?

“Business Adventures is as much about the strengths and weaknesses of leaders in challenging circumstances as it is about the particulars of one business or another,” says Gates. “In that sense, it is still relevant not despite its age but because of it. John Brooks’s work is really about human nature, which is why it has stood the test of time.”