Population growth, increasing affluence, technological change, and urbanization are all responsible for rapidly rising resource consumption all over the world. The relationship between population growth and increased resource use varies among developed and undeveloped nations. For example, according to the Department of Energy, residents of the industrialized world comprise only 20 percent of the world’s population, yet consume 86 percent of its iron and steel, and 76 percent of its timber. Despite the inconsistent relationship between resource use and developed and undeveloped nations, it is apparent that worldwide, more people use more resources. With popula tion, technology, and lifestyle demands growing exponentially, people are using increasing amounts of many natural resources.