Treatment of ovarian cancer involves surgery and chemotherapy. The decision of operability is made at the multidisciplinary conference. Prognosis depends not only in the stage and histological type of the tumor but also at the end result of surgery. Residual disease after initial surgery is a strong prognostic factor for survival, with improvement on both overall and progression free survival being greatest in women with no or minimal (tumor < 1 cm) visible disease at the end surgery. Supra radical surgery is a radical procedure plus e.g. extensive peritonectomy, resection of liver metastases, splenectomy, resection of the tail of pancreas and bowel resection. Only 60% of patients in advanced stage ovarian cancer are deemed optimal debulked peroperative. Patients with optimal debulking have a 5 year survival of 42% versus patients not possible of achieve radical operation with 5 year survival of 15%, resulting in a hazard rate of 2,12 for optimal vs. not optimal debulking. A correct preoperative assessment is important in planning of operation and to avoid futile operation in patients not resectable.