A couple weekends ago I joined Warren Buffett and 40,000 others in Omaha for Woodstock for Capitalists—a.k.a. the annual meeting of Berkshire Hathaway. As a shareholder and member of the board, I’ve been going for years and it’s always a blast. This time we had our usual fun, including a ping-pong match where Warren hit an impressive forehand winner against a former U.S. national champion. But the gathering had an extra resonance, because we had something special to celebrate: 50 years of Warren’s leadership at the company.

A lot has been written about Warren in the half-century since he took the reins at Berkshire. But I think the most interesting and insightful stuff is what Warren writes himself. Every year before the annual meeting, he puts together a letter to Berkshire’s shareholders in which he talks very honestly about what’s going well and what isn’t. He also reflects on investing and the economy more broadly. If you want to be as smart about business as Warren is—and who doesn’t?—you can’t beat those letters.

In this year’s letter, Warren takes a special look at the company’s past, present, and future. I cannot recommend it highly enough. It is the best and most important thing he has ever written. Warren’s partner, Charlie Munger, wrote his own letter and it is also excellent.

Warren and I took a break from the weekend’s events to spend a few minutes talking about his rules for smart investing, how he learned to explain complicated financial dealings so clearly, and how he got me into bridge and golf:

And here is a short post featuring some of my favorite photos of Warren from over the years.

Warren isn’t just a great friend. He is also an amazing mentor. I have been learning from him since the day we met in 1991. We discuss business, economics, politics, world events, and of course philanthropy—as a trustee of our foundation, he is a fantastic thought partner for Melinda and me.

Two years ago I wrote about three things I have learned from Warren. It boils down to this: He is always encouraging Melinda and me to tackle tough problems and have the courage to make mistakes. Luckily for Berkshire’s shareholders—and for everyone involved with the dozens of businesses in the Berkshire family—Warren follows this wisdom himself. For the better part of 50 years, he has been thinking big, and we are all better off for it.