Ultrasound has replaced X-ray as the main imaging modality for the diagnosis of pelvic floor disorders in women. Most recent developments -- volume contrast, speckle reduction and multi-slice imaging -- have markedly enhanced spatial resolution and ease of use, with the result that ultrasound now enables a cost-effective and non-invasive demonstration of bladder neck and pelvic organ mobility, vaginal, urethral and levator ani function and anatomy, and anorectal anatomy. The Atlas of Pelvic Floor Ultrasound provides an introduction to pelvic floor imaging as well as a resource to be used during initial and more advanced practice.