Breast surgery evolves towards always more precise, but less invasive techniques. The halstedian concept of radical surgery has been abandoned and the majority of patients are now allowed to preserve their breasts provided they receive radiation therapy after surgery. In many institutions standard axillary lymph-node dissection is being replaced by the less invasive and probably also more accurate staging technique known as sentinel-node dissection. Nevertheless, the procedure requires interdisciplinary collaboration and rigorous quality control monitoring to provide optimal results. Many issues, some of which will be discussed in the light of our personal experience, still need to be tested in clinical controlled trials.