The article presents a theoretical model of social consciousness developed from nurses' life histories. A 3-position dialectical framework--acquired, awakened, and expanded social consciousness--makes visible the way people respond to social injustice in their lives and in the lives of others. The positions coexist, are not hierarchical, and are contextually situated. A person's location influences her or his availability for social action. Nurses who could most contribute to challenging social injustices that underpin health disparities are relegated to the margins of mainstream nursing by internal processes of discrimination. More inclusive definitions of "a nurse" would open up possibilities for social change.