The demographic and economic transition that many developing countries are undergoing is producing important changes in diet and lifestyle that greatly impact on disease risks. Among the risk behaviors associated with socioeconomic transition and urbanization are excessive dietary fat intake, sedentary lifestyle, smoking, and environmental contamination. Combined with a reduced infant mortality and increased life expectancy, those risk factors lead to an increasing prevalence of chronic disease like non-insulin dependent diabetes and coronary heart disease. This disease. This disease profile is a relatively new phenomenon in developing countries, where health programs have traditionally focused on "acute" interventions such as immunization or oral rehydration. A new approach will be needed to address chronic diseases, which frequently demand a life-long and technically complex medical management, and may have significant impact on the quality of life and productivity of the population. Efforts to address this situation should focus on a) expanding the information base on diet, nutritional status and lifestyle changes in populations migrating to urban areas; b) developing and evaluating approaches for improving diet quality in urban populations, including fortification and community-based supplementation programs; c) understanding better the social and behavioral determinants of nutritional status in the urban poor; and d) defining the role of the food industry and of agricultural production for improving the quality of the food supply in urban areas.