In “The Environment and Breast Cancer,” we learn about “Windows of Susceptibility,” time periods in a life course that describe the heightened vulnerability of girls and women to breast cancer. A definition of “environmental risks” is offered, along with an overview of recent efforts to address substances linked to cancer risk, such as BPA, BPS and phthalates. Practical tips for protecting yourself and your family against these risky substances end the presentation, along with resources for further inquiry.