Although equipment for performance of robotic-assisted laparoscopic prostatectomy (RALP) is becoming more widely available, few surgeons have acquired the skill and experience necessary to master RALP. A significant issue has been the requisite training and experience (ie, the "learning curve") necessary for a qualified surgeon to become an expert at RALP. The senior author (J.A.S.) has experience with > 2500 radical retropubic prostatectomy (RRP) and > 350 RALP procedures. He assessed his learning curve in achieving expertise with RALP. Because there are no objective measures to define expertise with RALP, achievement of expert status depends on the surgeon's comfort, experience, and results with alternative approaches. Surgeons with extensive experience with open approaches may "set the bar" higher for the learning curve because of expectations. RALP results comparable to those obtained routinely with RRP were not achieved until after > or = 150 procedures. Surgeon comfort and confidence comparable to that with RRP did not occur until after 250 RALP procedures. Defining the learning curve for RALP as the point at which a surgeon could provide outcomes comparable to those obtainable with alternative surgical approaches means that the point varies, depending on the experience and expertise of the surgeon. Surgeons whose sole or dominant experience is with laparoscopic or robotic approaches may have a different perception of the learning curve compared with an experienced open surgeon.