The World Health Organization (WHO) defines health policy as those “decisions, plans, and actions that are undertaken to achieve specific health care goals within a society.”

The purpose of a health policy is to express an agency's vision of the future with respect to health care, outlining specific objectives for both the short and long term. It allows stakeholders to understand what the health priorities of an agency or organization are and how various individuals and organizations are involved in the actions of the healthcare organization.

In principle, the term health policy can apply to the long-term goals and mission of any healthcare agency or organization, although in practice it is most often used for the vision of states, nations, or even the international community as a whole. Perhaps the most common expression of the concept is in the area of personal healthcare policy, the determination by a state or nation as to how the health and wellbeing of individuals is to be managed. In some nations, for economic, political, historical, or other reasons, health care is regarded as an individual's private concern. When a medical needs arises, it is up to the individual to decide whether or not to see a medical professional, which professional to visit, and how to pay for those services. In other nations, a decision has been made that health care is the right of all citizens and that it is the duty of the national government to arrange for adequate care for all citizens, whether they can pay for it personally or not. Indeed, the view of the United Nations' Universal Declaration of Human Rights takes this position, noting that “everyone has the right to a standard of living adequate for the health and well-being of himself and of his family,” even in circumstances of old age, disability, sickness, or other circumstances beyond his or her control.

In the twenty-first century, virtually every developed nation in the world has adopted a health policy that reflects this view, agreeing to provide medical care that one needs whether or not a person can afford to pay for that care, a so-called “universal health care” approach. The one major exception to that rule is the United States, which remains committed to the proposition that individual citizens should have the right to make many, most, or all of their own healthcare decisions, even if it means that they must pay all or some of their own healthcare costs. Indeed, one of the most vigorous political debates in the United States in the second decade of the twenty-first century is centered on this question, with opposing forces arguing for a more government-centered program reflected in the 2010 Affordable Care Act, or a more decentralized program reflected in a variety of other healthcare options. Most experts believe that the current U.S. health policy is unsustainable in the long run because the financial costs of the existing system are greater than the federal government and individual citizens will be able to pay for in coming decades.

The term health policy is also used in a number of other contexts, usually in dealing with specific healthcare issues, such as aging , various specific diseases, disparities in access, systems of healthcare delivery, economics of health care, governmental programs (such as Medicare and Medicaid), mental health, prescription drugs, quality of care, tobacco and alcohol consumption, and health research. In each case the elements of a health policy are similar, with the need for decisions as to which aspects of a problem should receive priority, on what information decisions about the program should be made, what educational tools can be developed, how the program will be paid for, what individuals and organizations will be involved in the program, and how the results of the program will be assessed.

In addition to a host of books, reports, articles, and websites on the topic of health policy, a number of journals are devoted exclusively or primarily to this topic, including Health Policy (Elsevier), Journal of Public Health Policy (Palgrave), Health Affairs (Project HOPE), Health Policy and Planning (Oxford Press), Journal of Health Politics, Policy and Law (Duke University Press), Journal of Health Economics (Elsevier), American Journal of Public Health (American Public Health Association ), World Health Report (World Health Organization ), and Milbank Quarterly (Milbank Memorial Fund). Also, more than two dozen national organizations have a major interest in health policy issues and publish books, reports, articles, newsletters, and other materials on the topic. These organizations include the Alliance for Health Reform, Institute for Health Policy Solutions, the American Pharmaceutical Association, the American Association of Health Plans, the Center for Health Care Strategies, the Healthcare Leadership Council, and the Henry J. Kaiser Family Foundation.