In early surgical series, the incidence of positive lymph nodes in patients with prostate cancer was approximately 40%. In the modern era of screening and improved patient selection, the incidence is now <10%, although most series excluded patients with higher risk disease. The risk of having positive lymph nodes is influenced by disease stage, prostate-specific antigen level, and tumor grade and by the aggressiveness of lymph node dissection. Many of the same factors predict the outcome of these patients. Although the percentage of patients with positive lymph nodes has declined, there remain significant numbers of patients with lymph node-positive prostate cancer, and it remains a therapeutic dilemma. Cancer 2006. © 2006 American Cancer Society.