In this pilot study, we followed 22 patients during their psychoanalytic psychotherapy to monitor changes in the quality of their object representations (father, mother, partner/best friend, self) and level of psychopathology (OQ-45). The Differentiation-Relatedness Scale (DR-S) was used in two semi-structured interviews: Object Relation Inventory (ORI) and two questions of the Adult Attachment Interview (AAI). Results showed that the DR-S ratings are comparable in both interviews for father and mother, with significant changes during therapy for father using the ORI and mother using the AAI. The level of psychopathology also changed significantly during treatment. Despite some shortcomings, the DR-S in combination with the ORI and AAI-questions seems a useful instrument for clinicians to monitor structural change in personality functioning during psychoanalytic psychotherapy.