The need for new thinking in almost every aspect of our lives becomes ever more important as global populations expand and resources dwindle.   Water supply to our cities, ecological sustainability, and Australia's export future are just some of the issues which loom large within our rapidly changing world.  How we solve these problems will ultimately come down to our technological base and our willingness to face up to the scientific and economic realities of our changing world.  The question is, Is Australia ready to meet these challenges?