In conclusion, the prognosis for women with stage I borderline tumors is excellent. Surgery alone is the recommended treatment. For young patients, fertility-sparing surgery is optimal, with a small percentage eventually developing tumor in the contralateral ovary. For patients with advanced stage borderline tumors, 10-30% will relapse and approximately 10% will die of tumor. This risk is clearly higher for those with invasive peritoneal implants. Several controversies exist, including the classification of advanced stage serous borderline tumors and the issue of postoperative treatment. Future studies involving larger series and molecular biomarkers will hopefully elucidate the biologic behavior and optimal therapy for this interesting group of tumors.