Erikson's stages of psychosocial development. Erikson's stages of psychosocial development, as articulated by Erik Erikson, in collaboration with Joan Erikson, is a comprehensive psychoanalytic theory that identifies a series of eight stages, in which a healthy developing individual should pass through from infancy to late adulthood. All stages are present at birth but only begin to unfold according to both a natural scheme and one's ecological and cultural upbringing. In each stage, the person confronts, and hopefully masters, new challeng