人本主义的心理学大师马斯洛在1940年代提出的需求层次理论中，他将研究焦点放在心理健康的个体上，特别是那些所谓自我实现（Self-actualized）的人身上，尝试归纳出那些对生命感到满意、能发挥潜能又具有创造力的人的共通点。马斯洛发现，这些人之所以较不易受到焦虑与恐惧影响，是因为他们对自己及他人都能抱着喜欢及接纳的态度。他们虽然也有缺点，但因为能够接受自己的缺点，所以他们较一般人更真诚、更不防卫，也对自己更满意。

人本主义的心理学家及教育家相信每个人天生均具有自我实现的倾向，根据马斯洛的需求层级理论，当一个人较低层次的需求（如安全感）获得基本满足之后，他便会转而尝试满足更高层次的需求（如自我实现），对生命的满意度也随之提高。但是当这样的倾向受到阻碍时，特别是孩童时期遭受父母冷酷或拒绝的态度，便会影响到这个人自我概念的健康发展和他对现实世界的觉察，开始有自我防卫的意识，甚至从真实的感受中抽离出来时，更难成为自我实现的人。

Self-actualization is a term that has been used in various psychology theories, often in slightly different ways. The term was originally introduced by the organismic theorist Kurt Goldstein for the motive to realize one's full potential. Expressing one's creativity, quest for spiritual enlightenment, pursuit of knowledge, and the desire to give to society are examples of self-actualization. In Goldstein's view, it is the organism's master motive, the only real motive: "the tendency to actualize itself as fully as possible is the basic drive... the drive of self-actualization." Carl Rogers similarly wrote of "the curative force in psychotherapy – man's tendency to actualize himself, to become his potentialities... to express and activate all the capacities of the organism." The concept was brought most fully to prominence in Abraham Maslow's hierarchy of needs theory as the final level of psychological development that can be achieved when all basic and mental needs are essentially fulfilled and the "actualization" of the full personal potential takes place, although he adapted this viewpoint later on in life, and saw it more flexibly.