Wal-Mart, with its legendary focus on customer value in terms of price, is innovating in sustainability. Now, we're beginning to see the mirror image, a convergence, as the not-for-profit sector is beginning to serve more effectively by applying private sector accountability and efficiencies to social needs. This reflects a rising recognition that to serve others best requires more than good intentions; it mandates a focus on real-world results. Bill Gates and Warren Buffett are among the most conspicuous advocates and representatives of this transformation.

Curiously, for all the outpourings of scholarship on Theodore Roosevelt, no one had written a book focused directly on his leadership approach, working in large part from his own letters and other writings. That opportunity was open, and I was privileged to step in.

California is, in many respects, best understood as a nation-state. In the environmental-energy realm, California possesses far-reaching legal authorities that other states do not.

I often ask myself: "What would Theodore Roosevelt do?" One can never know, of course. The ultimate contribution of consequential leaders is often their capacity to reframe issues in novel ways. That said, his leadership engaged, at a foundational level, whether the American "national character" would accept decline and mediocrity, or would go all-in for leadership and excellence. Amid the myriad of otherwise disconnected issues before us, that choice is emerging yet again.

Theodore Roosevelt is a natural choice for leadership education. Along with many other observers, I believe he was among the greatest of leaders to serve as president.

I've benefited greatly from studying many effective people from history. Among those who've influenced me the most are Ronald Reagan, Theodore Roosevelt, and Winston Churchill. Each of the three altered history; each was self-created to a great extent; and each was a great student of history and leadership.

Ronald Reagan was unusual in being an authentic personality. Unlike many professional actors - and politicians - he was much the same behind the curtain as in front.