A mammogram is an x-ray picture of the breast. It can help detect breast cancer. While there is consensus among national health organizations about the benefits of routine mammogram screening in people 50 years and older, screening recommendations for average-risk individuals ages 40 to 49 years vary. In this Massachusetts General Hospital Blum Center presentation from October 28, 2021, Randy Miles, MD, MPH, examines the risks and benefits of routine breast cancer screening starting at age 40 at the individual level. He also discusses the role of advanced imaging techniques in screening patients on a population level.