The following data will be collected from patient charts: age at time of surgery, gravidity/parity, body mass index, pre-existing medical conditions/surgical history, current medications, menopausal status, form and severity of OAB symptoms, other previously or currently used interventions, method of SNM device placement, observed motor/sensory response, percent improvement of symptoms, follow-up OAB symptoms, frequency of InterStim settings adjustments, adverse events, significant changes in health, and incidence/reason for drop out.