Woodrow Wilson administration ended in tragedy, with his insistence on governing following his disabling stroke. I suspect President Wilson is often graded on a special curve, because many academic historians identify with him as one of their own.

There are people all around us whose lives are masterpieces of service. One thinks of parents working two or three jobs to serve their families and community. So, too, many in the military or in nursing or teaching. As the needs are endless, so are the possibilities of service. Now, more than ever, empowered by the Internet, more of us can serve in more ways than ever before in history.

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.

William McKinley has surely been underrated - in no small part because he was succeeded by a memorable leader, Theodore Roosevelt.

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.

Some critics have suggested that Ronald Reagan succeeded in a series of careers, ultimately as a two-term president of the United States, by a series of fortunate accidents. Such a criticism is not backed by the evidence. It is true, though, that Reagan's approach to work and life was not conventional.

Theodore Roosevelt is among the most captivating of presidents in our time, but his administration is often underestimated. Roosevelt's successes in domestic and international affairs are so wide-ranging as to appear obvious or inevitable in retrospect.