21st century Quote by Jeffrey Sachs

On an increasingly crowded planet, humanity faces many threats - but none is greater than climate change. It magnifies every hazard and tension of…

— Prince Charles

Our challenge, our generation's unique challenge, is learning to live peacefully and sustainably in an extraordinarily crowded world. Our planet is crowded to an…

— Jeffrey Sachs

The one common experience of all humanity is the challenge of problems.

— R. Buckminster Fuller

A united humanity will be able to confront the many troubling problems of the present time: from the menace of terrorism to the humiliating…

— Pope Benedict XVI

We must turn the greatest collective challenge facing humankind today, climate change, into the greatest opportunity for common progress towards a sustainable future

— Ban Ki-moon

The two major challenges for the 21st century are to improve the economic situation of the majority and save as much of the planet…

— E. O. Wilson

21st Century choice: Look after our planet and it will look after us, or don't and face the consequences

— Phil Harding

The fate of the living planet is the most important issue facing mankind.

— Gaylord Nelson

Our overriding environmental challenge tonight is the worldwide problem of climate change, global warming, the gathering crisis that requires worldwide action.

— William J. Clinton

In what I think is the most serious problem the world faces, which is the population explosion, we will come I think to a…

— Charlton Heston

Humanity is facing a challenge unlike any we've ever had to confront. We are in an unprecedented period of change.

— David Suzuki

I believe that the organisers of this conference have chosen a very timely subject for our discussion - because the 21st century will confront…

— Lord Robertson