"Self-actualization" is someone's tendency or desire to achieve his full potential. This term is most recognized as the highest-order need in Abraham Maslow's hierarchy of needs. It is just above self-esteem on Maslow's needs pyramid.
Self-actualization is often viewed as a target that is unattainable, because many people believe that there is always room to grow. However, several attributes are noted as being evidence of self-actualization. They include realistic expectations and acceptance of oneself, autonomy, solitude, appreciation or contentment and personal responsibility or ethics. One reason it is viewed as unattainable is that people demonstrating self-actualization traits constantly strive to better themselves.