Seemingly intractable problems of overpopulation, ecologic degradation, diminishing resources and regional warfare are having a profound effect on global population health. Canadian physicians can assist in ameliorating these problems by helping to modify the overconsumption of natural resources at home and by participating in international health projects focused at the community level, where the health of individuals and that of their environment intersect. The author describes the work of the Canadian Hunger Foundation in Vietnam and Sri Lanka, where a team of professionals worked with local farmers to improve the local water supply, decrease soil erosion and increase food production. The team observed changes in the physical health of communities that resulted in part from interventions that empowered them to address their own problems.