"The more money we spend, according to the GNP ... the better off we are," explains Eric Davidson in You Can't Eat GNP. The Gross National Product, or GNP in common parlance, is the cumulative value of products and services created and traded by a nation, and the traditional measure of economic well-being. Yet in the past decade or so, the flaws in this measuring system have become increasingly clear to a growing number of economists, social scientists, and other observers. As Davidson learned during his time as a Peace Corps volunteer in Zaire, not only does the GNP fail to account for the state of a country's health-care, education, and welfare systems -- it also fails to recognize the overall and long-term costs, environmental and otherwise, of producing goods and services.