It is hard to put a price on some things. What is the value of having prevented nuclear weapons from getting into the hands of a dictator like Saddam Hussein - or of Gadhafi?

There are things that we know, and there are things that we don't know. Then there are the things that we don't even know that we don't know. Those are the things that are the hardest.

Your performance depends on your people. Select the best, train them and back them. When errors occur, give sharper guidance. If errors persist or if the fit feels wrong, help them move on. The country cannot afford amateur hour in the White House.

One thing appears reasonably certain, and that's that those who make allegations of a culture of deception, of intimidation or cover-up need to be extremely careful about such accusations.

Enjoy your time in public service. It may well be one of the most interesting and challenging times of your life.

It is the photographs that gives one the vivid realization of what actually took place. (On photographs from Abu Ghraib prison.)

Control your own time. Don't let it be done for you. If you are working off the in-box that is fed you, you are probably working on the priority of others.