In order to distinguish different types of stress urinary incontinence with the help of urodynamics combined with ultrasound, a study was executed to find out if and how ultrasonographic variables in stress incontinent patients differ from healthy women. Various quantitative variables were defined and compared in the aforementioned groups. Craniocaudal and ventrodorsal related variables were the most discriminative in rest position. During coughing the same directional variables were also discriminative. The difference between stress and rest was significant only for the craniocaudal direction. The often discussed posterior vesical angle had no predictive value. The results of this pilot study support the concept that anatomical differences between stress incontinent patients and healthy women can be detected ultrasonographically. The study further indicates that stress urinary incontinence can be caused by a low rest position of the bladder neck or by a hypermobile bladder neck. Urodynamics combined with ultrasound probably can be applied to distinguish more precisely different types of stress urinary incontinence.