Résumé : Objectives: To investigate the impact of "on-demand" clamping during laparoscopic partial nephrectomy on warm ischemia time. Methods: We retrospectively reviewed 39 consecutive patients with renal tumors who had undergone transperitoneal laparoscopic partial nephrectomy from April 2002 to May 2006. Median tumor size was 2.3 cm. In all cases, the hilum was dissected early and extracorporeal clamping performed. The pedicle was clamped only in case of excessive bleeding, and it was released immediately after the closure of the renal defect with knot-tying sutures over Surgicel bolsters. Results: Median operative time was 120 min. Renal clamping was required in 31 of 39 patients and in this subgroup the median warm ischemia time was 9 min. Median operative blood loss was 150 ml. Eight patients required blood transfusion and among these two were converted to open surgery. Positive surgical margin was observed in one case. Renal cell carcinoma was present in 22 (54.4%) specimens. No recurrence was observed after a median follow-up of 15 mo. Conclusions: This novel technique using extracorporeal clamping significantly decreases warm ischemia time, avoiding clamping of the pedicle in selected cases. Our study underlines the feasibility of performing laparoscopic partial nephrectomy with extracorporeal hilar clamping, allowing the shortest ischemia time ever published. © 2007 European Association of Urology.