Individuals with posttraumatic stress disorder (PTSD) related to a serious motor vehicle accident were randomly assigned to either group cognitive behavioral treatment(GCBT) or a minimum contact comparison group (MCC).Compared to the MCC participants (n=16), individuals who completed GCBT (n=17) showed significant reductions in PTSD symptoms, whether assessed using clinical interview or a self-report measure. Among treatment completers, 88.3% of GCBT participants did not satisfy criteria for PTSD at posttreatment assessment, relative to31.3% of the MCC participants. Examination of anxiety,depression, and pain measures did not show a unique advantage of GCBT. Treatment-related gains were maintained over a 3-month follow-up interval. Patients reported satisfaction with GCBT, and attrition from this treatment was comparable with individually administered CBTs.Results are discussed in light of modifications necessitated by the group treatment format, with suggestions for future study of this group intervention.