Erik Erikson's psychosocial theory of development proposes that people pass through eight stages of development from infancy to late adulthood. In each stage, individuals face a psychosocial crisis that helps shape their identity and personality. The stages involve developing trust, autonomy, initiative, industry, identity, intimacy, generativity, and integrity. Successful completion of each stage leads to healthy development and ability to transition to the next stage. Erikson's theory views development as occurring throughout the entire lifespan rather than just childhood.