Psychoanalysis began with the concept of psychic trauma, which was subsequently not clearly differentiated from traumatic object loss or from unconscious conflict and fantasy. Psychic trauma is investigated in relation to unconscious conflict, with and without concurrent object loss. The syndromes of PTSD, uncomplicated by object loss, of traumatic bereavement, and of relatively nontraumatic bereavement, though often interwoven and inseparable, are all different. The significance of the loss, sociocultural factors, and group process influence individual responses to trauma and traumatic bereavement. There are specific neurobiological and psychological sequelae of traumatic experience. Clinical applications are noted.