The containment of health care expenditure is one of the major challenges facing public policymakers in the developed countries. This paper provides evidence of significant differences in the crosscountry level of efficiency of health care expenditure, meaning that potential cost savings for the countries considered least efficient might be very high. Further, a significant relationship is found between the various health care policies and institutions in the OECD countries and the efficiency levels of health care systems. The findings are, however, highly sensitive to the efficiency-estimation methodology used.