Leininger developed the ethnonursing research method to study transcultural human care phenomena using her theory of culture care diversity and universality. The ethnonursing research methodology which uses an open, largely inductive process of discovery to document, describe, understand, and interpret people’s meanings and experiences will be presented. The ethnonursing researcher functions as co-participant with informants working together to discover how people experience and practice care in their daily lives. Systematic and reflective processes are used while focusing on the cultural context to explicate lifeways and understand their meaning for informants. The ethnonursing method embraces the importance of discovery from the people’s ways of knowing (generic care) and gives credence to the professional nurse’s way of knowing (professional care). Both generic and professional care have been discovered to provide assistance and supportive care for the health and wellbeing of people or to help people face death or disabilities. The authors’ research related to cultural competence and culturally congruent care will be provided to demonstrate how the use of this theory and method have contributed to discipline knowledge and nursing practice, education, research, and administration. Future directions for the use of the ethnonursing research method with the culture care theory will be presented.