The removal, cryopreservation, and subsequent reimplantation of ovaries would make it possible to treat a young cancer patient and improve her quality of life by preserving her fertility. The current technology requires cutting the ovary into pieces before freezing and does not support preservation of the whole ovary. The ovary has a complex endocrinologic function. It is composed of cells of different form and character and contains oocytes at various stages of development. Successful cryopreservation, transplantation, and functional rehabilitation of the whole ovary would have broad significance, not only for ovaries but also for other organs such as the liver, kidney, and heart. Ovarian cryopreservation technology would lead the way to the establishment of a biological bank for frozen internal organs.