Ultrasonography (US) is the method of choice for the diagnosis of bladder disease. It is superior to other imaging techniques, such as urography and cystography, in depicting certain structures and abnormalities. US examination of the bladder should include a study of the ureterovesical junction and the structures round the vesical neck. The examination technique may be transabdominal, transrectal or transvaginal, or transurethral. The bladder pathology that can be studied by US includes cystitis, calculi, clots, diverticula, trauma and tumors. The sensitivity and the specificity of the method are very high and sometimes superior to cystoscopy. Sonography can be used to explore patients with stress incontinence and those with abdominal trauma. The ureterovesical junction may be clearly examined by US and the pathology of the papilla clearly defined.