The relationship between Kernberg's psychodynamic model of personality organization (PO) and dissociation has not yet been explored. Seventy-two nonclinical subjects and 222 psychiatric patients completed the Dissociative Experiences Scale and the Inventory of Personality Organization. Its Reality Testing subscale emerged as the most important predictor for all facets of dissociation. Discussing our results in the framework of Fonagy and coworkers' model of mentalization, we suggest that dissociation may reflect the preoedipal "pretend" mode of psychic functioning while impaired reality testing and psychotic experiences might be indicative of the "psychic equivalent" mode.