Based on data from the NICHD Study of Early Child Care and Youth Development (N = 1,149), the current article provides the first large-sample investigation of associations between different forms of infant attachment insecurity and dissociative symptomatology from childhood through midadolescence as measured by scales based on the mother, teacher, and youth self-report versions of the Achenbach System of Empirically Based Assessments. Findings did not replicate the previously reported and highly cited evidence that infant attachment disorganization is associated with dissociative symptomatology. In contrast, correlations of small magnitude were observed between infant avoidance and dissociative symptomatology, as assessed by teachers and mothers (but not self-report). Results were not moderated by contextual risk. Limitations of the study included the absence of measures of maltreatment and interpersonal trauma, leaving open the possibility that infant attachment disorganization is a diathesis for later dissociation in the context of severe and/or chronic trauma. Nevertheless, the present results strongly indicate the need for additional research exploring the possible role of environmental factors in the development of dissociative symptomatology.