The state of health of the world population has costantly improved in recent years. However, quality of life and life expectancy show huge variations in the different demografic regions of the world. To explain such differences three main factors can be considered: 1 - patterns of disease, which are largely determined by geography and climate; 2 - human behaviour; 3 - health services funding, organization and management. The paper develops a discussion on these issues, focusing on correlation between health systems methods of funding and management and state of health of the world population.