Over the course of my career working for nonprofits, I have gotten to know and work with dozens of billionaires.

One of my favorites is Alan Parker.

Mr. Parker grew up in a middle-class family in Rhodesia where his dad was a civil servant. He trained as an accountant and went to work for a Hong Kong-based company called DFS: Duty Free Shopping. When DFS it was sold in 1997, Mr. Parker received $840 million.

Mr. Parker is one of the most generous, intelligent and philanthropic billionaires I’ve ever met.

Unlike most billionaires who spend little time, money or effort on philanthropy, Mr. Parker and his entire family have been vigorously engaged in philanthropy since 1983.

Unlike most foundations that distribute as little as legally possible, Alan Parker’s Oak Foundation gives away a staggering $200 million every single year.

That’s more than half a million dollars every single day.

It goes to a broad range of non-profits all around the world. The Oak Foundation has six main programs: Environment, Prevent Child Sexual Abuse, Housing, and Homelessness, International Human Rights, Issues Affecting Women, and Learning Differences. A “Special Interest” program. And four national programs: Brazil, Denmark, India, and Zimbabwe.

Every year, for almost 10 years, at Smile Train and then at WonderWork, we received a $50,000 annual grant from the Oak Foundation.

And every year, for almost ten years, we would submit a final grant report explaining how we used their grant. I always offered to fly to Geneva to thank Mr. Parker for his generous support also. (And tell him more about our programs!) The answer was always thanks but no thanks.

But one year, after I sent in a very emotional final grant report that included a trip I took to Africa, I received a call from Mr. Parker’s assistant.

“Mr. Parker wants to know if you do any work in Zimbabwe.” I responded immediately, “We don’t – but we could. We’d love the opportunity to start working in Zimbabwe.”

One month later I got the meeting I had waited 10 years for.

I was sitting in a conference room at the Oak foundation offices in London, sitting across from Mr. Parker and his daughter Natalie. They were both extremely gracious, intelligent, and interested in our work. They even took me to lunch afterward which was greatly appreciated.

That meeting turned into a very generous $450,000 grant which would help provide more than 1,600 blindness and burn surgeries in Zimbabwe. After 10 years of $50,000 a year grant.

I guess the lessons I learned from this experience were to never give up, always send final grant reports even if you don’t know if anyone will read them and when opportunity knocks, jump on it.

My tremendous respect and admiration for Alan Parker, his family, and his Oak Foundation only increased after we went through their rigorous but fair grant application program and we got to know and work with some of the terrific folks on their team.

If more billionaires were like Alan Parker and more foundations were like The Oak Foundation, the world would be a very different place.