Dissociation reflects disruptions in the integration of memories, perception, and identity into acoherent sense of self, and may develop following childhood maltreatment. The preschool yearswere identified as an important period for the development of dissociation. However, priorresearch has not examined the development of dissociation during this time. In order to addressthis gap, evidence of dissociation in 45 maltreated children, assessed for sexual abuse, physicalabuse, and neglect, was compared with dissociation in 33 nonmaltreated children. Rather thandepend on adult observer reports of behavior, the study sought to gain an understanding ofdissociation from the child's own point of view. Because self-reports have limitations withsuch young children, a measure of dissociation evidenced in children's narrative story-stemcompletions was utilized. Maltreated children, especially physically abused children and sexuallyabused children, demonstrated more dissociation than did nonmaltreated children. Moreover,during the preschool period maltreated and nonmaltreated children followed different trajectoriessuch that dissociation increased for maltreated children but did not do so for nonmaltreatedchildren. Findings suggest that although the self is normatively integrated during the preschoolperiod, it becomes increasingly fragmented for some maltreated children. Results are discussed interms of cascading effects of maltreatment throughout development, and the importance ofdevelopmentally sensitive interventions.