The aim was to study whether patients with panic disorder with agoraphobia and co-occurring Cluster C traits would respond differently regarding change in interpersonal problems as part of their personality functioning when receiving two different treatment modalities. Two cohorts of patients were followed through three months' in-patient treatment programs and assessed at follow-up one year after end of treatment. The one cohort comprised 18 patients treated with "treatment as usual" according to psychodynamic principles, the second comprised 24 patients treated in a cognitive agoraphobia and schema-focused therapy program. Patients in the cognitive condition showed greater improvement in interpersonal problems than patients in the treatment as usual condition. Although this quasi-experimental study has serious limitations, the results may indicate that agoraphobic patients with Cluster C traits should be treated in cognitive agoraphobia and schema-focused programs rather than in psychodynamic treatment as usual programs in order to reduce their level of interpersonal problems.