This document provides an overview of Dorothea Orem's Self-Care Deficit Nursing Theory. It describes Orem's background and education, her nursing experiences, theoretical influences, and the three interrelated theories that make up her general theory of nursing: the Theory of Self-Care, Theory of Self-Care Deficit, and Theory of Nursing Systems. It also provides an example of applying Orem's theory to assess a patient's self-care deficits and plan appropriate nursing care.