Chronic diseases are increasing in global prevalence and seriously threaten developing nations' ability to improve the health of their populations. Although often associated with developed nations, the presence of chronic disease has become the dominant health burden in many developing countries. Chronic diseases were responsible for 50% of the disease burden in 23 high-burden developing countries in 2005 and will cost those countries $84 billion by 2015 if nothing is done to slow their growth. The rise of lifestyle-related chronic disease in poor countries is the result of a complex constellation of social, economic, and behavioral factors. Variability in the prevalence of chronic disease is found both at the country level and within countries as differences in risk factors are observed. This upward trend is forecast to continue as epidemiologic profiles and age structures of developing countries further shift. More research is needed to identify a full range of prevention-focused, cost-effective interventions against chronic diseases in the developing world.