We review sentinel lymph node biopsy in patients with high-risk melanoma. This method of selective lymphadenectomy provides valuable staging information about the regional lymphatics without the need of prophylactic complete lymph node dissection. Only patients with micrometastases are candidates for complete lymph node dissection. This avoids, in nearly 85% of patients, the morbidity of the more extensive procedure. In addition, sentinel lymph node–positive patients may qualify for adjuvant therapy protocols. Whether this surgical approach ultimately results in a survival advantage awaits the results of a National Cancer Institute–sponsored national multicenter trial. (J Am Acad Dermatol 1998;39:603-10.)