This research represents the first controlled treatment study of hypnosis and cognitive- behavioral therapy (CBT) of acute stress disorder (ASD). Civilian trauma survivors (N = 87) who met criteria for ASD were randomly allocated to 6 sessions of CBT, CBT combined with hypnosis (CBT-hypnosis), or supportive counseling (SC). CBT comprised exposure, cognitive restructuring, and anxiety management. CBT-hypnosis comprised the CBT components with each imaginal exposure preceded by a hypnotic induction and suggestions to engage fully in the exposure. In terms of treatment completers (n = 69), fewer participants in the CBT and CBT-hypnosis groups met criteria for posttraumatic stress disorder at posttreatment and 6-month follow-up than those in the SC group. CBT-hypnosis resulted in greater reduction in reexperiencing symptoms at posttreatment than CBT. These findings suggest that hypnosis may have use in facilitating the treatment effects of CBT for posttraumatic stress.