Much recent attention has focused on the development and refinement of pain measures, as well as on the use of more effective pain control methods for infants, children, and adolescents. This article reviews the primary categories of pediatric pain measures, with a specific focus on the selection of the most appropriate behavioral, physiologic, or subjective method for assessing a child's pain. The optimum pain measure depends on the age and cognitive level of a child, the type of pain experienced, and the situation in which the pain occurs. While no single measure is adequate for all children for all types of acute, recurrent, and chronic pain, it is possible to choose practical, valid, and reliable methods for evaluating any child's pain experience.