Primary cytoreductive surgery remains the standard care in advanced ovarian cancer. Optimal cytoreductive surgery is defined as a residual tumor load less than 1 cm. after operation. The randomized clinical trials showed that interval debulking surgery improved survival in patients who did not undergo optimal primary debulking surgery. The retrospective trials have suggested that the outcome for patients treated with neoadjuvant chemotherapy followed by interval debulking surgery is the same as for patients treated with primary debulking surgery followed by adjuvant chemotherapy. The neoadjuvant chemotherapy should not to be used for clinical practice until the randomized clinical trial carried out by Gynecological Cancer Group of the European Organization for Research and Treatment of Cancer and National Cancer Institute of Canada answers this question. There are no data from randomized trials to show the survival advantage in patients who received second-look operation as compared to those who did not.