PIP: This article reports the author's field investigation into the effects of economic development on environmental health in Rwanda. It was hypothesized that the placement of environmentally hazardous industry would not be given meaningful consideration in the course of the introduction of advanced technolgies. Rwanda is a poor, overpopulated country with a subsistence economy whose development has been largely stimulated by international aid projects. Site visits to industrial and agricultural processing facilities revealed significant perticide exposure, lack of respiratory protection from mineral dusts, respiratory symptoms from organic dusts, and sources of heavy metal contamination. The Rwanda experience suggests that 2 major economic activities are most likely to have a major environmental impact in developing countries: exploitation of natural resources and agricultural commercialization. Mining activity, for example, has produced both chronic diseases such as silicosis and general environmental degradation such as runoff to surface water sources. The use of agricultural petrochemicals is likely to produce acute and chronic poisoning among peasant farmers with little access to adequate health care. Even the smallest industrial installation can have widespread impact if the proper infrastructure for waste treatment is not established. In addition, the technology required to test for environmental contamination is beyond the scope of Third World economies. Hazardous environmental exposures may have amplified or additive effects in the presence of compromised baseline health and sanitary conditions and inadequate health care facilities. It is concluded that Rwanda represents an example of the failure of economic developers to consider the far-reaching effects of changes in the work environment, introduction of new agricultural techniques, alteration of the rural-urban equilibrium, and degradation of the air, water, and soil quality. There is a need to adapt models of environmental protection in industrialized developed countries to developing economies.