Acute stress disorder (ASD) is a good predictor of posttraumatic stress disorder in adult populations, although the emphasis on dissociation symptoms within the diagnosis has been questioned. Recent studies suggest that ASD may also have application to children and adolescents. The present study examined properties of ASD within youth. A large (N = 367) multisite sample of 6- to 17-year-old children and adolescents exposed to motor vehicle accidents completed interviews or self-report questionnaires regarding their acute stress symptoms. The study found evidence supporting the suggestion that the dissociative criterion of ASD is excessively strict in youth, and that there is less overlap between dissociative symptoms than in adults. The implications of these findings for how ASD is applied to youth are discussed.