Excellent methods are available to produce quality images of the liver and kidneys. Gray scale echography is the only suitable method of simultaneously showing hepatic and renal anatomic detail in addition to the instantaneous relationship of these organs to each other. Gray scale echography may be used to determine (1) if normal liver and a normal right kidney have interacted to give the false clinical impression of disease, (2) when renal lesions simulate hepatic disease, (3) when hepatic lesions mimic renal disease, and (4) if structural hepatic and structural renal disease are related or unrelated.