The borderline syndrome was reexamined recently in a new comprehensive way. We present a diagnostic reevaluation of chronic ward patients who were formerly diagnosed and treated as chronic schizophrenics. A new, meticulous clinical assessment, as well as psychological testing, suggested the borderline-syndrome diagnosis. These patients represent a special category of borderline patients not hitherto described and a characteristic etiological background was found in their familial constellation. A causal and descriptive differentiation between these patients and schizophrenics is mandatory: careful investigation of backward populations in hospitals might reveal numerous similar cases (borderlines in this special category). They call for a different, definite line of treatment.