Freud's concept that the dream protects sleep is first applied to a clinical vignette involving combat veterans and then re-examined. Although conceived in the context of the topographical model, it is more compatible with the structural model. The mind produces a believed hallucination mimicking gratification of impulses that would lead to awakening. It is hypothesized that the dream develops in the neonate during the arousal of the REM state to protect sleep from burgeoning object-directed impulses. The clinical vignette suggests that traumatic dreams can use past trauma to insure current vigilance. Traumatic memories may symbolize fantasy complexes in dreams.