Just finished reading this outstanding book by David Gergen. Never mind that I started this more than a year ago. Read a couple of chapters here and there. Finally completed it yesterday.
David Gergen served on the White House Staff of four US Presidents: Nixon (as head of speech writing); Ford (Chief of Communications); Reagan (Director of Communications) and Clinton (Counselor). Considering that he served Republican and Democratic Presidents, tells more of Gergen's centrist philosophies. He debated Mark Shields beautifully on the MacNeil/Lehrer Newshour. More than getting his point across, he aspired to educate the audience with his well positioned opinions.
In this book he offers behind-the-scenes accounts of the goings on in the White House, and analyses the strengths and weaknesses of each President. Drawing upon these experiences, he offers a well thoughtout Leadership Guide to future leaders.
It is not one of those books which you can speed read. I would read a chapter, take a break, digest it, and then move on. His language is exquisite, and thats why I would read some paragraphs again and again. My copy is marked up with sections I would want to go back to, as a reference. If you think of ever harnessing your leadership potential, start here.
Arun Shanbhag 
Thanks Cyroceon;
Despite having read the book so many years ago, I still admire and turn to it.
Best.
Great book, I admire Gergen for his outstanding recount of his time close to the most powerful leaders in the latter part of the 20th century.