Society increasingly expects physicians to consider costs when making medical decisions. Eisenberg discusses clinical economics techniques that physicians can use for comparing options in medical practice. He defines three types of economic analysis, and identifies four points of view toward costs, outcomes, and benefits: society's, the patient's, the provider's, and the payer's. He reviews four types of costs that can be included in economic analysis of medical care: direct medical costs, direct nonmedical costs, indirect morbidity and mortality costs, and intangible costs. Eisenberg also discusses the use of sensitivity analysis to determine the degree to which uncertainty and potential bias could influence decisions about the economic impact of medical decisions. He believes that by understanding economic analysis, physicians will be able to act as patient advocates and fulfill their responsibilities to society to manage resources prudently.