OBJECTIVE To evaluate the clinical and urodynamic results achieved by transvaginal bladder denervation (the Ingelman technique) for bladder instability refractory to anticholinergic therapy. METHODS The Ingelman procedure was performed in 14 female patients in whom anticholinergic therapy was unsuccessful or contraindicated. The mean age was 53.3 years (range 21-71 yrs.) and the most common presenting symptom was urge incontinence. Bladder instability persisted in 7 patients (involuntary contractions throughout the filling phase), bladder compliance was less than 30 ml/cm H20 in 7 and bladder capacity less than 300 ml in 8 patients. RESULTS There were no intra or postoperative complications. The mean postoperative follow-up was 10.9 months (range 2-41). One patient was lost to follow-up. RESULTS 10 patients (71%) reported cessation or decrease of symptoms ('clinical improvement'), 2 referred the same symptoms and 1 claimed to be worse. Urodynamic results: Some urodynamic parameters had improved in 6 of the 10 patients with clinical improvement; however, only 3 had a normal urodynamic study. Some urodynamic parameters (bladder capacity, compliance and first micturition sensation) had become worse in the 3 patients that showed no clinical improvement. There was no statistically significant improvement of the mean values of any urodynamic parameter. CONCLUSIONS Transvaginal bladder denervation is a simple and safe procedure. In this series, it has achieved symptomatic improvement in 70% of patients with bladder instability. Urodynamic improvement was observed in only 3 of these patients (21%). Patients with no clinical improvement also showed worse urodynamic data postoperatively.