In recent years there has been a renewed interest in the integration of descriptive and interpersonal approaches to mental illness. Much of the impetus for this stems from the introduction in 1980 of the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition (DSM-III) (American Psychiatric Association 1980), with subsequent research and clinical reports documenting important interactions between Axis I syndromes and Axis II personality trait factors. While many research efforts have described comorbidity in affective and anxiety disorders, less attention has been directed toward clarifying the relationships between stable and enduring character traits and Axis I symptoms in schizophrenia. In this paper we propose that schizophrenic patients display both adaptive and pathological personality traits throughout the illness, and that clinical and research efforts to address the interactions between syndromic and personality factors ("trait-state" interactions) will further our understanding of patterns of symptom presentation and treatment response in these patients.