Economic outcomes are increasingly important in cancer research. This article provides an introduction to the nature and measurement of economic outcomes in cancer and gives the reader entry points to a considerable literature on measuring economic endpoints in health and medicine. Economic outcomes data are defined here as measures of resources consumed in prevention, detection, and treatment of cancer and its sequellae. Part I of this essay discusses the questions addressed by economic outcomes. Part II presents a typology of and introduction to measurement of economic outcomes. Part III discusses important measurement issues and calls for development and validation of standardized protocols and questionnaires to measure economic outcomes, especially at the patient level.