Rapid population growth is the fundamental cause of the world's environmental problems. Most scientists agree that population growth plays an important role in a wide variety of environmental problems, since, all things being equal, a larger population will consume more resources and produce more wastes than a smaller one. But factors such as economic growth, technological change, and government policies also play important roles. Because many of the critical variables depend on one another, it is difficult to isolate the impact of a single variable such as population. Choice of technology also depends on affluence.
Rich countries are better able to invest in pollution control and environmental remediation.
In addition, government policies, markets, and institutions may either disguise or amplify the effects of other variables such as population. For example, the same pressures that lead to soil degradation in one country may prompt measures to protect soil quality in another. However, it is clearly a significant factor and a serious problem. In reality, international family planning efforts are part of a comprehensive strategy to promote reproductive health care and to prevent unplanned or ill-timed conception. International programs funded by the United States support basic contraceptive services provided by both governments and the private sector, including supplying contraceptives and helping to train health workers and managers.