With a fixed amount of water on earth, a growing population means the competition for water is increasing.

Americans are using less water now than they were 30 years ago. Yet, there never seems to be enough to go around. One billion people worldwide are without safe access to drinking water. What role can President-elect Obama play in alleviating the world's global water crisis? Peter H. Gleick, an acknowledged water authority and president of the non-partisan research group, The Pacific Institute, offers some suggestions.