We present our results with the use of transurethral injection of polytetrafluoroethylene (Teflon) in 128 female patients with moderate to severe urinary incontinence from 1964 to 1991. Of the patients 60% had undergone previous surgical treatment for the incontinence. The etiologies included stress incontinence, neurogenic bladder, congenital anomalies, trauma and others. More than 73% of the patients improved (54.3% were totally dry). The failure rate was 27%. Complications were minimal. Urinary tract infection and temporary urinary retention occurred in 7 and 6 patients, respectively. Mean followup was 31 months. This study demonstrates that transurethral polytetrafluoroethylene injection is a useful treatment of moderate to severe urinary incontinence in female patients. Polytetrafluoroethylene is particularly useful for patients with failed previous incontinence procedures and poor surgical candidates. Failures are more likely in patients with periurethral fibrosis secondary to a previous urethral operation.