The clinical and urodynamic findings in 1,193 consecutive women referred for investigation of urinary incontinence and other urinary symptoms were reviewed. Impaired bladder emptying was defined as a repeated maximum flow rate below 15 ml/second or a residual urine volume of 150 ml or more. One hundred and sixty-five women were diagnosed as having voiding dysfunction. Fifty-six of the 165 women (34%) had a residual urine volume of 150 ml or more. Voiding dysfunction was the only abnormal urodynamic finding in 27 women and was associated with genuine stress incontinence, detrusor instability or bladder hypersensitivity in a further 138 patients. Overflow incontinence was diagnosed in 7 women (0.5%). Symptoms of impaired bladder emptying were significantly more common in women with proven voiding dysfunction but were absent in a third of these patients. One in 4 women with normal micturition had symptoms of voiding difficulty. Neurological disease, pelvic surgery and psychological factors were important causes of voiding dysfunction. Voiding disorders are a common cause of lower urinary tract dysfunction and should be an important consideration in future patient management.