PIP: 2 of the possible links between national income and national health status have attracted particular attention. A strong statistical association exists between national per capita income and such indicators of national health status as infant mortality rates and life expectancy, suggesting some broad causal nexus between high incomes and better health. 2nd, the national accounts provide a convenient framework for defining the share of a country's resources which is devoted to health services, either through the public or the private sector, how these resources are provided and financed, and who are the beneficiaries. Either of these types of relationships between income level and health may have much significance for the development of health on a global scale--the improvement of the health status of the populations of the developing countries. Data and discussion regarding the international distribution of income and its implications for health and direct national comparisons of purchasing power and their implications for health lead to the following conclusions about policy toward health development in the 3rd world: 1) using the presently available health care approaches, there is reason to expect substantial improvement in health status in the developing countries by the year 2000 based on the following factors--the growth of per capita incomes for reasons external to the health sector, any additional increases in the per capita resources devoted to health care, and improvements in the efficiency with which inputs are applied in the health sector so as to bring all countries up to the level of the currently most efficient; and 2) foreign assistance to the health sector will be most effective if it concerns current rather than capital inputs and it takes the form of money or scarce equipment rather than the services of health personnel. Given data limitations these conclusions are tentative and lead to further outlined recommendations.