Perspectives in an economic analysis of medical technology reflect who makes decisions about the use of or payment for medical resources. Commonly used perspectives include those of providers, insurers, the individual, and society. Perspective is a critical determinant of study design, affecting the time horizon, types of resources considered, and economic cost measures assigned to those resources. Individuals involved in technology assessment for either research or policy-making purposes should be aware of the complexities of defining costs from different perspectives.