This study sought to investigate the following research questions: Are time-limited day treatment programs for patients with personality disorder (PD) effective outside resourceful university settings, and what are the overall treatment results when the program is implemented on a larger scale? Do all categories and subtypes of PDs respond favorably to such treatment? How intensive should such day treatment programs be? All patients (n = 1,244) were consecutively admitted to eight different treatment programs in the Norwegian Network of Psychotherapeutic Day Hospitals from 1993 to 2000. Altogether, 1, 0 10 patients were diagnosed with PD. Avoidant, borderline, not otherwise specified (NOS), and paranoid PD were the most common conditions. SCID-II and MINI were used as diagnostic instruments. Outcome measures included GAF Global Assessment of Functioning, (GAF; American Psychiatric Association, 1994), SCL-90R, CIP, Quality of Life, work functioning and parasuicidal behavior, measured at admittance, discharge and 1-year follow up. The attrition rate was 24%. The number of dropouts did not improve over time. As a group, completers with PD improved significantly on all outcome variables from admittance to discharge and improvement was maintained or increased at follow up. Treatment results were best for borderline PD, cluster C patients, PD NOS and No PD, and poorer for cluster A patients. Units with a high treatment dosage did not experience better outcomes than those with a low treatment dosage (10 hours per Week). Results from the University unit were not better than those from units at local hospitals or mental health centers.