Book excerpt: Three of the factors that most directly affect the potential for sustainability - population, technology, and lifestyle - are discussed and analyzed in-depth. In addition, the authors examine global patterns of income distribution and the pressing need for greater equality between the northern and southern hemispheres. The authors, all leading scholars in their fields, argue that traditional means of economic growth which rely on an ever-increasing use of energy and natural materials cannot be sustained. They advocate an imaginative pursuit of economic ends that are less resource intensive and allow for increases in quality of life without corresponding decreases in environmental quality.