Da Vinci robot-assisted radical prostatectomy: initial experience in 50 consecutive cases Objective: To report our initial experience in 50 cases submitted to a Robotic Radical Prostatectomy (RRP), evaluating results and the learning curve. Material and Methods: From january to october 2010 we performed 50 consecutives cases of RRP with the da Vinci S-HD Surgical System®. The database was performed prospectively, and was analyzed retrospectively. We evaluate demographic data (age, body mass index) and perioperative data such as clinical stage, preoperative PSA (Prostate Specifi c Antigen), Gleason Score, ASA, operative times, estimated blood loss, morbidity, hospital stay, time of bladder catheterization and positive margins. A statistical analysis of exponential regression was performed to estimate the learning curve. Results: The mean age was 62 years and the most frequent clinical stage was T1c (84%). The mean PSA was 6.36 ng/mL and in 50% of the patients the Gleason Score was 7. The median surgical time was 199 minutes. The mean blood loss was 666 mL (50-4.000 mL). The hospital stay and the average bladder catheterization time were 2 and 6 days, respectively. There were 2 conversions to a laparoscopic approach, none to open surgery, and 8% of postoperative complication (all Clavien 1). Inmediat urinary continence and potency rates were 88.3% and 33.3%, respectively. When comparing the 25 initial cases versus the last 25, there was a decrease in surgical time and estimated blood loss (254 minutes vs 189 minutes and 876 mL vs 467 mL, respectively). We also found a lower rate of positive margins (20% vs 12%). The learning curve statistically estimated is 40 procedures. Conclusion: The surgeon's experience determine a decrease in surgical time, intraoperative bleeding and especially in the rate of positive margins.