The world is getting warmer. Among scientists concerned with global climate change this is the broad consensus. How fast and by how much, are questions which cannot be answered quantitatively, but the probability of rising temperatures must be faced in a prudent manner - there is enough certainty of change so that we must anticipate and prepare before irreparable damage is done to our world. Even if it isn't going to be as bad as some people think, the actions we propose will benefit the earth and give us a kind of insurance. The root of the change is population growth, and its attendant demand for energy. While the developed world expects to hold future emissions relatively steady, the developing countries, where population growth is most rampant, will expand the use of energy as they aspire to a better quality of life. H greater energy use is inevitable it behooves us to produce that energy in the least objectionable manner, and to produce it where the cost is lowest in dollars, GNP, and environmental change.