After all, sustainability means running the global environment - Earth Inc. - like a corporation: with depreciation, amortization and maintenance accounts. In other words, keeping the asset whole, rather than undermining your natural capital.

Anyone who is seriously interested in me would usually do a little more homework and realise that the extreme criticisms are almost exclusively ideologically based.

I believe we are going to move into a situation where the more effective conferences will be smaller, more specialized, more focused, with occasional large gatherings to get the attention of the larger world.

Nevertheless, the concept of sustainable development is now known - even amongst those who haven't accepted it - and it's recognized, debated and followed by an increasing number of businesses.

We're either going to save the world or no one will be saved.

I am President of the UN created University for Peace, which has a strong commitment to the relationship between peace, security and the environment. I meet with young people around the world and I always come away enthused and encouraged.

I was with Ted Turner when he came to see Kofi Annan - the Secretary-General of the UN - to announce his decision to put $1 billion to the service of UN projects and programs.