Dr. Paterson and Dr. Zderad developed the theory of Humanistic Nursing after meeting in the 1950s while working at Catholic University. They published their book on the theory in 1976. The theory views nursing as a dialogical, transactional relationship between nurse and patient aimed at promoting patient well-being and potential. It uses a phenomenological approach to understand patients' lived experiences. Paterson and Zderad conducted research applying this approach to understand why some psychiatric patients remained in day treatment while others left.