Mammography is currently the most effective method for detecting or ruling out breast cancer. It involves taking an X-ray at low tube voltage, allowing for high soft-tissue contrast. Special high-resolution, high-sensitivity film-screen systems are also used. Each breast is usually imaged in two views and compressed in the mammography device. This compression can sometimes be uncomfortable but is essential for accurate assessment. Mammography is particularly effective in older women, whose normal breast tissue has partially regressed. Malignant tumors appear as dense shadows, and tiny calcifications (so-called microcalcifications) are often found near malignant tumors, which can only be reliably detected with mammography. This allows the detection and safe treatment of even the smallest, non-palpable tumors. For this reason, mammography is currently the most effective method for preventive screening. Balancing benefits against radiation exposure, the German Society of Senology currently recommends a baseline mammography for women starting at age 40, followed by a one-year follow-up and subsequent checks every two years. As an additional method, especially important for younger women, breast ultrasound can provide crucial diagnostic information. This should be performed according to the individual findings of the patient. There is also a relatively new method, MR mammography, which uses magnetic fields to clarify findings that cannot be definitively assessed by other imaging methods.