This article discusses many elements of suicide, including definitions of various types of self destructive behaviors, Durkheim’s types of suicide, Freud & Menninger’s theories on suicide, & biological factors (particularly the connection between suicide & serotonin). As well, the author outlines predictors of suicidality such as depression, hopelessness, mental & physical illness, substance abuse, age, sex, prior attempts, & social isolation. (VM)