The Nursing Need Theory was developed by Virginia Henderson and was derived from her practice and education. Henderson's goal was not to develop a theory of nursing, but rather to define the unique focus of nursing practice. The theory emphasizes the importance of increasing the patient's independence so that progress after hospitalization would not be delayed. Her emphasis on basic human needs as the central focus of nursing practice has led to further theory development regarding the needs of the patient and how nursing can assist in meeting those needs.

Henderson identifies three major assumptions in her model of nursing. The first is that "nurses care for a patient until a patient can care for him or herself," though it is not stated explicitly. The second assumption states that nurses are willing to serve and that "nurses will devote themselves to the patient day and night." Finally, the third assumption is that nurses should be educated at the college level in both sciences and arts.

The four major concepts addressed in the theory are the individual, the environment, health, and nursing.

According to Henderson, individuals have basic needs that are components of health. They may require assistance to achieve health and independence, or assistance to achieve a peaceful death. For the individual, mind and body are inseparable and interrelated, and the individual considers the biological, psychological, sociological, and spiritual components. This theory presents the patient as a sum of parts with biophysical needs rather than as a type of client or consumer.

The environment is made up of settings in which an individual learns unique patterns for living. All external conditions and influences that affect life and development. The environment also includes individuals in relation to families. The theory minimally discusses the impact of the community on the individual and family. Basic nursing care involves providing conditions in which the patient can independently perform the fourteen components explained in the model.

There are fourteen components based on human needs that make up nursing activities. These components are:

1. Breathe normally. Eat and drink adequately.
2. Eliminate body wastes.
3. Move and maintain desirable postures.
4. Sleep and rest.
5. Select suitable clothing. That is, dress and undress appropriately.
6. Maintain body temperature within normal range by adjusting clothing and modifying the environment.
7. Keep the body clean and well groomed and protect the integument.
8. Avoid dangers in the environment and avoid injuring others.
9. Communicate with others in expressing emotions, needs, fears, or opinions.
10. Worship according to one's faith.
11. Work in such a way that there is a sense of accomplishment.
12. Play or participate in various forms of recreation.
13. Learn, discover, or satisfy the curiosity that leads to normal development and health and use the available health facilities.

These components show a holistic approach to nursing that cover the physiological, psychological, spiritual, and social. The first nine components are physiological. The tenth and fourteenth are psychological. The eleventh component is spiritual and moral. The twelfth and thirteenth components are sociological, specifically addressing occupation and recreation.

The theory's definition of health is based on an individual's ability to function independently as outlined in the fourteen components. Nurses need to stress the promotion of health and prevention, as well as the curing of diseases. According to Henderson's model, good health is a challenge because it is affected by so many different factors, such as age, cultural background, emotional balance, and others.

Henderson's definition of nursing states: "I say that the nurse does for others what they would do for themselves if they had the strength, the will, and the knowledge. But I go on to say that the nurse makes the patient independent of him or her as soon as possible." The nurse is expected to carry out a physician's therapeutic plan, but individualized care is result of the nurse's creativity in planning for care. The nurse should be an independent practitioner able to make independent judgments as long as he or she is not diagnosing, prescribing treatment, or making a prognosis, since those activities are the function of the physician.

Henderson explains in The Nature of Nursing that the role of a nurse is "to get inside the patient's skin and supplement his strength will or knowledge according to his needs." The nurse has the responsibility to assess the needs of the patient, help him or her meet health needs, and provide an environment in which the patient can perform activity unaided.