Four hundred and sixty-five women attending a urodynamic clinic were interviewed, and completed a detailed bowel questionnaire, about their urinary and bowel symptoms. All the women underwent video-cystourethrography with pressure and flow studies. The reported incidence of faecal incontinence was 15.3% (n= 71) on direct questioning and 26% 0(n = 121) on the postal questionnaire. Faecal incontinence was more common in women with a urodynamic diagnosis of detrusor instability (30′%1 (n= 26)) than among women diagnosed as having genuine stress incontinence (21% (n= 38)). Denervation and myogenic injuries sustained during childbirth have been suggested as a common cause for genuine stress and faecal incontinence, but there may be an alternative mechanism to explain why women with detrusor instability suffer from faecal incontinence.