Disease staging of patients with breast cancer is based on the probability of metastatic disease, the reliability of complementary examinations, and therapeutic possibilities, evaluated on a cost/benefit basis. For regional disease staging, nodal status can be assessed by ultrasound, and the value of this approach can be optimized by imaging-guided biopsies. Ultrasound examination of nodes upstream of the sentinel node allows determination of the utility of this node and the indications for axillary resection. Work-up of metastatic spread is performed only after evaluation of risk factors for metastasis. Prior to therapy, and in the absence of any clinical warning signs for resectable tumors, there are no indications for imaging, which is reserved solely for locally advanced tumors.