The treatment of ovarian cancer should be appropriate, since clinical and surgical decisions may affect the prognosis; the surgery must be performed by an expert oncological surgeon or gynecological oncologist, it's fundamental roles are cancer staging and cytoreduction. The concept of staging surgery in early stages has its justification in the fact that up to 11% of "early ovarian cancers" will have metastasis in different sites of the peritoneal cavity at the time of diagnosis. In advanced stages of epithelial ovarian cancer, the goal is the complete cytoreduction of all visible macroscopic disease, since this variable is the most strongly associated with increased overall survival and disease-free period. The ideal time for cytoreductive surgery in relation to chemotherapy (before or after) is still under debate. In 2010 a randomized trial (EORTC) was published, comparing 310 patients initially operated (followed by adjuvant chemotherapy) versus 322 patients initially treated with neoadjuvant chemotherapy (followed by cytoreductive surgery); no significant differences in overall survival between groups were found. Another important factor playing a role in survival and in the probability of surgical cytoreductive success is tumor biology; there has been described a clear difference between serous and mucinous tumors, but some groups advocate that maximal surgical effort in mucinous tumors may compensate morbidity with an increase in survival. The extension of resection in cytoreduction is still controversial; some authors have confirmed that the most important factor is the residual disease and that radical surgery is superior to non-radical surgery in terms of overall survival. The need and extent of lymphadenectomy in advanced cancer will be treated in another chapter of this issue. Undoubtedly, an important factor is to perform procedures in specialized centers.