My most important projects have been the building and maintaining of schools and medical clinics for my dear friends in the Himalaya and helping restore their beautiful monasteries, too.

I have enjoyed great satisfaction from my climb of Everest and my trips to the poles. But there's no doubt that my most worthwhile things have been the building of schools and medical clinics.

I enjoyed climbing with other people, good friends, but I did quite a lot of solo climbing, too.

The Sherpas play a very important role in most mountaineering expeditions, and in fact many of them lead along the ridges and up to the summit.

Good planning is important. I've also regarded a sense of humor as one of the most important things on a big expedition. When you're in a difficult or dangerous situation, or when you're depressed about the chances of success, someone who can make you laugh eases the tension.

I believe that of all the things I have done, exciting though many of them have been, there's no doubt in my mind that the most worthwhile have been the establishing of schools and hospitals, and the rebuilding of monasteries in the mountains.