Background and Purpose: Conical blunt trocar insertion may eliminate the need for fascial closure (FC) in transperitoneal laparoscopic renal surgery. This concept applies to 12-mm blunt trocar placement through muscular parts of the abdominal wall, relying on muscle splitting and eventual muscle retraction when the trocar is removed. We retrospectively assessed the safety of fascial nonclosure (FNC) after 12-mm blunt port insertion. Patients and Methods: Ninety transperitoneal laparoscopic renal procedures were performed between August 1999 and May 2000. Four ports (two 12 mm and two 5 mm) were usually used except for 30 donor nephrectomies, where an additional 5-mm port was used. The 12-mm trocars were inserted at the lateral border of the rectus muscle 5 cm below the costal margin and in the anterior axillary line 8 cm below the costal margin. Fascial closure was performed in 62 patients and nonclosure in 28 patients. Exclusion criteria for FNC included midline location, malnutrition, renal failure, and chronic use of steroids. Postoperative outcomes were compared in 20 patients with FNC matched with 20 patients with FC. Results: At an average of 4.8 months of follow-up, none of the patients developed a trocar site hernia. No significant statistical differences were observed between the groups with regard to intraoperative and postoperative data. Conclusions: These two approaches appear to be equivalent in terms of patient morbidity and postoperative hospital stay. Fascial nonclosure after transperitoneal 12-mm blunt trocar insertion, through muscular parts of the abdominal wall may be safe and efficacious and eliminates the last step in transperitoneal laparoscopic renal surgery.