Erik Eriksons theory of psychosocial development proposes that personality develops in a predetermined order through eight stages, from infancy to late adulthood. Each stage is characterized by a psychosocial crisis, which is a conflict between two opposing forces, and the resolution of this conflict determines the individuals psychological development. The eight stages of psychosocial development are:

1. Trust vs. Mistrust (birth to 1 year)
2. Autonomy vs. Shame and Doubt (1 to 3 years)
3. Initiative vs. Guilt (3 to 6 years)
4. Industry vs. Inferiority (6 to 11 years)
5. Identity vs. Role Confusion (adolescence)
6. Intimacy vs. Isolation (young adulthood)
7. Generativity vs. Stagnation (middle adulthood)
8. Ego Integrity vs. Despair (late adulthood)

Erikson believed that the results from each stage, whether positive or negative, influence the results of succeeding stages. The successful resolution of each stage results in the development of a psychological strength or virtue that helps the individual navigate future challenges.