This chapter discusses the major reproductive tract cancers that occur in the human population. In males, evidence for risks of testicular and prostate cancer as a function of exposure to endocrine disrupting agents is examined while in females, cancers of the breast, ovaries, and endometrium is evaluated. In men, chronically elevated estrogens have been associated with increased risk of prostate cancer. Similar to the prostate, breast cancer is a hormonally driven cancer and one major identified risk factor for breast cancer is an increased lifetime exposure to estrogens. Unlike ovarian cancer, endometrial cancer presents with symptoms such as unusual vaginal bleeding, abnormal discharge, and pelvic pain. Since a major risk factor for endometrial cancer is estrogen action unopposed by progesterone, exposure to estrogens or estrogen agonists from pesticides, herbicides, and other environmental contaminants have the potential to play a role in endometrial cancer initiation or promotion.