Roger Federer

It’s no secret that Roger Federer is the greatest tennis player ever. As David Foster Wallace wrote, he is “one of those rare, preternatural athletes who appear to be exempt, at least in part, from certain physical laws.” He also seems exempt from the laws of aging. At 36, he’s still winning Grand Slams with a combination of grace and grit.

But not as many fans know about what Roger is doing off the court. Twice I’ve had the thrill of being his doubles partner to help raise money for his foundation, and we’ve become friends in the process. I’ve learned how sincerely Roger and his team are working to improve the life prospects for poor children—a mission that stems from his childhood visits to his mother’s home country of South Africa and seeing extreme poverty firsthand.

Roger knows that effective philanthropy, like great tennis, requires discipline and time. It will be a sad day for all of us fans when he hangs up his racket—but we can take comfort in knowing that he’s committed to making the world a more equitable place.

Gates is a co-chair of the Bill & Melinda Gates Foundation