The overall cost of medical care is high and creates a major burden for societies and governments. Nevertheless, healthcare economics does not necessarily entail cost reduction but rather is concerned with how to use resources more effectively. When choices are made in the alternative usages of resources, ethical decision-making is mandatory. For this reason, doctors should include budget in their decision-making process and decide if it is worthwhile spending extra money on a minor improvement in individual treatment rather than spending on health benefits for the whole community. However, there is no definitive determinant between benefit to the patient and social cost, and it may not be easy to achieve balance. Physicians will increasingly face more clinical guidelines, new administrative programs, managers/politicians who are under pressure and burdened with urgent business, and more well informed patients. Therefore, they should understand the principles and methods of clinical economics in order to ethically use new information about both the cost and the impact of clinical practice. As far as doctors critically evaluate data on cost and effectiveness, they may be able to preserve their roles not only as advocates of their patients but also as responsible members of hospitals, healthcare organizations, and society in general.