The author attempts to complement the usual view of splitting in phenomenological and psychodynamic terms. His hypothesis, based on ego psychology, includes three main concepts: 1) information processing style; 2) self and object schematization; and 3) patterns of interpersonal manipulation. He defines splitting, mentions ways in which the patient responds to the therapist, particularly the borderline patient, and, utilizing a case report, describes many of the permutations and combinations seen in the transference-countertransference interactions in the therapeutic situation. Splitting, which is more common in borderline patients, is seen, although less prominently displayed, in neurotic patients, and will be found to a greater or lesser extent in all patients.