Although courage is an important variable when clients successfully deal with hospitalization and illness, the concept is contradictory and ill-defined in nursing and other literature. The phenomenological approach and research method has been suggested as one means of concept clarification and theory development. Using the phenomenological approach, this study asked: What is the essential structure of the lived experience of courage in chronically ill adolescents? Nine chronically ill adolescents participated in an open-ended, audiotape-recorded interview, describing their subjective experiences of courage. The descriptions were analyzed phenomenologically. Significant statements were extracted, meanings formulated, and themes identified. Thirty-one theme clusters in nine categories emerged from which an essential structure of courage in chronically ill adolescents was derived.