KIE: The concept of essential health care postulates that there is a set of basic services that should be available to all who need care, with more services obtainable by those who want and can afford to purchase them. Eddy discusses the difficulties with putting the concept of a basic level of care into practice: the lack of operational definitions for 'essential care' and 'basic services', and the need to appoint decision makers who will determine if a particular treatment is essential. He argues for the need to decide about benefits, harms, and costs when determining an intervention's essentialness, and for the importance of having these decisions made by patients. Eddy identifies methodological issues that need resolution, and offers observations on the ethical implications of providing different levels of care for different persons, and of having health care policies decided by a small group of people.