Two-polarities models of personality propose that personality development evolves through a dialectic synergistic interaction between two fundamental developmental psychological processes across the life span--the development of interpersonal relatedness on the one hand and of self-definition on the other. This article offers a broad review of…

Self-inflicted injury (SII) in adolescence marks heightened risk for suicide attempts, completed suicide, and adult psychopathology. Although several studies have revealed elevated rates of depression among adolescents who self injure, no one has compared adolescent self injury with adolescent depression on biological, self-, and informant-report…