The technique of transperitoneal inguinal herniorrhaphy evolved its principles for success through the process of continuous quality improvement. Between December 21, 1989 and December 20, 1993, 278 patients had repair of 348 inguinal and/or femoral hernias using any of four transperitoneal methods. Group I had mesh repair of only the visualized defect; Group II had mesh support of the entire inguinofemoral area; Group III had staple fixation of mesh as in Group I; whereas Group IV had staple fixation of mesh as in Group II. Recurrence rates were 23% in Group I at 4 years, Group II had 6% at 3(1/2) years, Group III had 33% at 3 years, and Group IV had 0% at 3 years. On average, patients returned to unrestricted activity in 4.5 days. The most significant complication was that of small bowel obstruction secondary to partial or complete peritoneal flap dehiscence. These continuously scrutinized data resulted in elucidation of the principles of successful repair. They include, complete dissection and mesh coverage of the entire inguinofemoral area regardless of where the visualized defect presents, staple fixation of mesh to prevent its displacement, and close reapproximation of the peritoneal edges. For the past 3 years, adherence to these principles has resulted in 0% recurrence rates and prompt resumption of activity.