There is growing international evidence that the effectiveness of health services stems primarily from the extent to which the incentives facing providers and consumers are aligned with "better health" objectives. Efficiency in health service provision requires that providers and consumers have incentives to use healthcare resources in ways that generate the maximum health gains. Equity in at least one sense requires that consumers requiring the same care are treated equally, irrespective of their ability to pay. Efficiency in the use of health services requires that consumers are knowledgeable about the services on offer and which are most appropriate to their needs. Although these principles are enshrined in the design of every health system in the world, they have proven extremely difficult to apply in practice. Healthcare providers have financial obligations to their families as well as professional obligations to their patients. Health service consumers generally lack information about both their health and health services so that they under-consume or over-consume healthcare.