So goes the saying and so arrives the first aspect of change. Understanding can provide motivation and motivation is necessary for change.
'Dawn of a thirsty century' by Alex Kirby and published by BBC News Online might help us consider turning off the faucet.
The amount of water in the world is limited. The human race, and the other species which share the planet, cannot expect an infinite supply.
Water covers about two-thirds of the Earth's surface, admittedly. But most is too salty for use.
Of what is left, about 20% is in remote areas, and much of the rest arrives at the wrong time and place, as monsoons and floods.
Humans have available less than 0.08% of all the Earth's water. Yet over the next two decades our use is estimated to increase by about 40%.