Abstract
In spite of extreme differences in health status between the more developed and less developed countries, trends of infant mortality and life expectancy show substantial improvements in both types of country between 1950 and 1980. These improvements may be attributed to three types of change: 1) socio-economic development with decolonization, increased industrialization, growth of gross domestic product, urbanization, the gains of women, and enhanced education; 2) cross-national influences due to greater international trade, the spread of technology, and widespread affirmation of human rights; and 3) national health system development through expanded governmental health programs. Further improvements will depend on greater strength in public sector health services rather than private sector services which aggravate inequities.