Effective nursing practice is based on an understanding of the theoretical basis of nursing. Similarly, to be effective patient educators, nurses must be familiar with the theoretical basis of patient and family education. Theories provide the framework from which nurses use tools that can be adapted to each patient. Nurses may educate their patients and families using any combination of theories to achieve best results. Through this process arises the opportunity for the achievement of optimal patient outcomes. This article highlights theories originating from communications, psychology, education, sociology, and nursing.