Although sentinel lymph node biopsy is now the primary method of axillary staging and is therapeutic for patients with limited nodal disease, axillary lymph node dissection (ALND) is still necessary for staging in groups where sentinel lymph node biopsy has not been proven to be accurate and to maintain local control in those with a heavy axillary tumor burden. Additionally, newer approaches to systemic therapy tailored to risk level sometimes necessitate knowledge of the number of involved axillary nodes which can only be obtained with ALND. Ongoing trials will address whether there are additional circumstances where radiotherapy can replace ALND.