Transurethral resection of bladder tumour is a common procedure (10,711 new cases of bladder tumour diagnosed in France in 2000), associated with a certain morbidity. Intra- or extraperitoneal perforation of the bladder wall is a possible complication. The diagnosis is generally established intraoperatively and cystography can be performed in the operating room to demonstrate the diameter of the perforation. Most cases of extraperitoneal perforation can be treated conservatively by simple bladder drainage. Intraperitoneal perforations may require surgical repair Laparoscopy is currently tending to replace open surgery for this repair. One of the risks of perforation is also tumour seeding outside of the bladder However metastases related to perforation appear to be rare and occur rapidly requiring close surveillance.