This book encompasses the results of two decades of research on locoregional spread of gynecologic cancer, which put forth the ontogenetic cancer field model and its clinical translation in terms of ontogenetic tumor staging and cancer field surgery, particularly for carcinomas of the lower female genital tract. The ontogenetic cancer field model describes the propagation of malignant tumors within distinct permissive tissue regions determined by the development of the tissue from which the neoplasm originated. As the morphogenesis of multicellular animals proceeds stepwise through bifurcational cell fate specification within tissue regions dictated by the positional identity and plasticity of the precursor cell populations, tumor formation during malignant progression occurs as a stepwise process in the reverse direction with regard to positional identity and plasticity. This principle of order can be exploited for diagnosis, treatment and prognosis of cancer in general. The motivation to study in depth the topography of tumor spread arose from the insight that the conventional view of local cancer propagation as an unlimited isotropic process is falsified by numerous inconsistencies with clinical facts. Consequently, conventional cancer therapy based on this model cannot achieve optimal outcomes. The cancer field model and its application in gynecologic oncology has been published in highly ranked journals. However, the complexity of the principles and practice need the format of a well-structured book for their successful transmission to gynecologic surgeons, clinical oncologists, cancer researchers and postgraduate medical students.