This paper attempts to provide a few guidelines of use to the nurse in assessing the pain experience in children inasmuch as there still exists a paucity of literature on the assessment and management of pain in children. The study of pain is of great relevance to the pediatric nurse, who must understand the different variables that affect the perception and expression of pain in children in order to be able to intervene appropriately. Information pertinent to the assessment of pain using developmental, psychologic, and cultural variables has here been presented. In addition, assessment tools that have been developed and tested on children have been listed and discussed. The intent is to sensitize pediatric nurses to the variables involved in the care of children in pain and to encourage them to examine the multitude of research questions that need answering. Only when these questions have been answered scientifically can we begin to solve some of the mysteries of pain in children.