Regional lymph node dissection (LND) at the time of radical cystectomy is an essential component of the surgical management of invasive bladder cancer and might provide diagnostic and therapeutic benefits for both node-negative and node-positive patients. The benefits obtained in pathologically node-negative patients might result from more complete resection of undetected micrometastases or from a more meticulous surgical technique. Advanced nodal disease also seems to be amenable to thorough surgical resection in a subpopulation of patients with bladder cancer. Despite the growing body of evidence to support the role of a more extended LND, no guidelines regarding the optimal boundaries of LND have been established. An increased number of resected nodes and wider LND boundaries have been associated with improved local disease control and prolonged survival. Additionally, mapping series indicate that the common iliac and presacral nodal regions are more frequently involved with tumor metastases than previously recognized. Efforts to limit any unnecessary dissection in patients at low risk for metastases--a tailored approach--has been proposed, but remains unproven. From the available evidence, the most reliable diagnostic and therapeutic approach to LND includes the routine extended LND in all patients undergoing cystectomy with curative intent.