Self-acceptance is defined as affirmation or acceptance of self in spite of weaknesses or deficiencies.
Although this term has been often understood in a common sense way, researchers have defined it formally in terms of positive and negative self-concepts. According to Shepard (1979), self-acceptance refers to an individual's satisfaction or happiness with himself, and is thought to be necessary for good mental health. Self-acceptance involves self-understanding, a realistic, albeit subjective, awareness of one's strengths and weaknesses. It results in an individual's feeling about himself that he is of "unique worth".
In clinical psychology and positive psychology, self-acceptance is considered the prerequisite for change to occur. It can be achieved by stopping criticizing and solving the defects of one's self, and then accepting them to be existing within one's self. That is, tolerating oneself to be imperfect in some parts.
Shepard, L. A. (1979). Self-acceptance: The evaluative component of the self-concept construct. American Educational Research Journal, 16(2), 139-160.