Nurses intuitively recognize an optimistic outlook as a personality component that has a positive impact on clients' health‐related behavior. Optimism, however, has not been studied from the perspective of nursing. The author did a concept analysis of optimism (the first step in grounding the study of optimism in nursing practice); identified attributes, antecedents, and consequences; and developed a definition of optimism. A case study contrasts examples of a model, borderline, and contrary positions and illustrates their difference