Although dissociation is often described as a posttraumatic response, the actual statistical association between trauma exposure and dissociative symptoms is surprisingly small. This suggests that that some dissociative phenomena may be unrelated to trauma, or may be related in more complex ways. Analysis of the normative data for the Multiscale Dissociation Inventory revealed significant dissociative symptoms in only 8% of trauma-exposed individuals from the general population. However, 90% of those with at least one clinically significant dissociation scale on the Multiscale Dissociation Inventory reported a trauma history, and significant dissociation was found in only 2% of nontraumatized individuals. A history of interpersonal violence, number of different types of trauma exposure, posttraumatic stress, and affect dysregulation were univariate predictors of dissociative symptomatology in trauma-exposed participants, but only posttraumatic stress and affect dysregulation were multivariate predictors. Trauma is probably an important, but insufficient, condition for the development of dissociative symptomatology. Additional risk factors, such as high posttraumatic stress and/or reduced affect regulation capacities, may determine whether trauma exposure results in clinically significant dissociation.