Ultrasound has the advantage of being able to visualise fluid-filled structures without the need for contrast medium. It can demonstrate soft tissue structures such as the kidney, bladder wall, urethral and anal sphincters and surrounding pelvic floor musculature. Use of the transabdominal, transvaginal, transrectal and transperineal approaches for ultrasound scanning allows for easy visualisation of different aspects of the lower urinary tract. Bladder diverticula are easily visualised with transabdominal ultrasound. Transvaginal ultrasound allows clearer visualisation of the bladder base, bladder neck, inferior border of the pubic symphysis and periurethral structures. Translabial ultrasound is used to demonstrate uterovaginal prolapse. Three-dimensional ultrasound offers new insights into the pelvic floor as it allows imaging of both the levator ani muscle hiatus and paravaginal support structures in axial and transverse planes. This gives access to transverse planes similar to magnetic resonance imaging.