In 1990 the Worldwatch Institute in Washington estimated that humankind had forty years to make the transition to an environmentally stable society. If we have not succeeded by then, it concluded, environmental dterioration and economic decline are likley to be feeding on each other, pulling us into a downward spiral of social disintegration. Worldwatch is no millenarian cult, but a sober and careful organisation whose annual summaries of world affairs have become the planet's unofficial environmental health reports. Its pronouncements are cautiously worded, influential and worth attnedning...