Radical cystectomy and lymphadenectomy is an accepted standard of care for muscle-invasive bladder cancer. Although the absolute limits of lymphadenectomy have not been standardized a growing body of evidence supports an improvement in nodal staging and survival from an extended lymphadenectomy. The benefit has been reported for both node negative and node positive patients. This review focuses on lymph node mapping, factors that influence total lymph node count and the optimal number of lymph nodes that should be removed at lymphadenectomy. © 2009, SAGE Publications. All rights reserved.