Industrialization: Demographic Transition Theory.

This article is an overview of demographic transition theory. It outlines the differences between the four main stages of the demographic transition and explains what factors help countries move from one stage to the next. It also considers whether some developed nations have moved into a fifth stage of the demographic transition (in which population will decline) and discusses some of the consequences of such a change in terms of the economy and immigration. Population pyramids as a research tool for studying the demographic transition are presented, as is a discussion of trends in global population change. Finally, the article discusses current controversies around the continuing applicability of demographic transition theory to less-developed countries in a time of HIV and other global epidemics as well as continued global population growth.