Need

A need is the psychological feature that arouses an organism to action toward a goal and the reason for the action, giving purpose and direction to behavior.

The most widely known hierarchy of needs was proposed by Abraham Maslow. In it, he proposed that people have a hierarchy of needs, which range from security to self actualization. However, while this model is intuitively appealing, it has been difficult to operationalize it experimentally. It was further developed by Clayton Alderfer.

The academic study of needs was at its zenith in the 1950's, but receives scant attention today. One exception is Richard Sennett's work on the importance of respect. The concept of intellectual need has been studied in education.

Marshall Rosenberg's model of Compassionate Communication also known as Nonviolent Communication (NVC) makes the distinction between universal human needs (what sustains and motivates human life) and specific strategies used to meet these needs. In contrast to Maslow, Rosenberg's model does not place needs in a hierarchy. In this model, feelings are seen as indicators of when human needs are met or unmet. One of the intended outcomes of Rosenberg's model is to support humans in developing an awareness of what life-sustaining needs are arising within them and others moment by moment so that they may more effectively and compassionately find strategies to meet their own needs as well as contribute to meeting the needs of others.

People also talk about the needs of a community or organization. Such needs might include demand for a particular type of business, for a certain government program or entity, or for individuals with particular skills.