Ovarian cancer has the worst prognosis of all gynecologic cancers. Overall 5-years survival approximates 40%, mainly due to the large proportion of patients presenting with advanced disease. In the Netherlands with a population of 16 million people, there are 1,100 new patients each year, implying one to two new cases per year for every gynecologist. The treatment of ovarian cancer is multidisciplinary in nature. Optimal management of ovarian cancer patients van improve survival. The studies presented in this thesis address some heavily debated issues in daily clinical practice and were performed to provide a stronger scientific rationale for choices in treatment strategies for ovarian cancer patients.