Health care systems in transition: confronting new problems in changing circumstances.

This essay introduces a series of articles in which authors from Brazil, China, the Netherlands, and New Zealand describe their health care system. The juxtaposition of these four case studies reveals how different systems confront common problems. The four systems use widely differing combinations of the same financing tactics, and all are engaged in limiting inefficient increases in health services expenditures. Thus, they face the common problem of obtaining sufficient knowledge to convince health care professionals and the public that they have the ability to eliminate less cost-effective procedures and control the pace of medical innovation. This series also illustrates how the economic differences between countries result in different resource allocations for health care expenditures. The case studies underscore the fact that health systems must mount a country-specific response to common health challenges. Thus, health care providers must provide the most cost-effective, equitable, and acceptable health care possible within the parameters of their society.