This single case study illustrates a methodology for identifying recurrent pathological emotional states in a hospitalized, borderline patient. Parallel therapeutic inputs are delineated and examined in terms of patient-specific responses. The results indicate that ratings of nursing notes recorded across three periods of hospitalization can reliably isolate the patient's most salient and debilitating emotional states. State-specific therapeutic interventions are extracted and their effectiveness noted. The analyses illustrate clinical phenomena which are congruent with what is known about borderline symptomatology. In addition, the study locates therapeutic errors which often occur when working with difficult patients.