This is the first article written by this group of authors/researchers who are collaborating on the development of the Oucher, an assessment tool to assist 3- to 12-year-olds describe the intensity of pain. The background and conceptual framework for its development, the research supporting the validation of the original Oucher, the research to create new ethnic versions, and the basic instructions for clinical use are described. In addition, several issues regarding the continued development and use of the Oucher are identified, including those relative to poster size and the gender and ethnicity of the photographed child. This article illustrates the precision and care needed to create clinically useful tools for obtaining information directly from young children.