David Koch was a friend of mine, and America is poorer today after his death last week.

The tributes are pouring in, mostly highlighting his incredible record of philanthropy and political engagement. It’s true that David was extraordinarily generous, giving away more than a billion dollars to the arts and medicine, especially cancer research. It’s also true that he was active in policy debates, advocating the principles that enable human flourishing. In all his endeavors, David wanted to help others have a better shot at the best life.

But one part of David’s life is getting short shrift — the biggest part of his life. David Koch was an exceptional business leader, the kind we need more than ever.

David embodied the concept of principled entrepreneurship. It’s a way of doing business, best articulated by his brother Charles, that links your success with how much you help others succeed. Sure enough, just as David sought to help others in his philanthropy and policy efforts, he worked relentlessly to deliver better prices, better quality and a better life for his customers.

Nearly all of David’s career was spent in New York City, running the engineering component of the family business, Koch Industries. When he started as its president in the late 1970s, it was a small slice of the company. By the time he retired, nearly 40 years later, he had grown the company nearly 50-fold. Over that same time, it went from a few hundred employees to more than 5,000.

Companies only grow like that when they’re doing something right. For David Koch, the right thing meant finding new ways to benefit others. His brother Charles has said that David “wanted to focus on those areas where he could make the greatest contribution.”

And what a contribution he made.

David helped turn Koch Industries, a small company focused mostly on serving energy refiners, into a worldwide corporate leader in pollution prevention and environmental standards. This is a story that’s rarely told, but that matters to hundreds of millions of people in America and across the world.

The results speak for themselves in the company’s success. David wanted every dollar his company earned to come from delivering a measurable improvement in the customer’s life, and that’s exactly what he pursued. Whatever benefit he got came from the benefit gained by others.

Imagine if future business leaders followed this model. Imagine if they looked for long-term gains, as opposed to quick bucks. Imagine if they tied their own success to the success of their customers, rather than focusing solely on helping themselves, no matter who they hurt.

Most Americans distrust business because many corporate leaders are transparently self-dealing and self-serving. They see a corporate culture that ignores the mutual benefit at the heart of America’s free-market system. And yet there was David Koch, quietly and consistently showing the better way — the path of principled entrepreneurship. His life is a case study in business done right.

By all means, let’s praise David Koch for his amazing generosity and involvement in public life. But let’s also remember the difference he made in the private sector. The best thing we can do to remember David is to imitate his example, especially those of us in business. The more people who do, the better off our country will be for everyone.

Tim Busch is the founder and CEO of the Pacific Hospitality Group.