Nephrosonography has become a useful diagnostic tool in assessing renal disease. Parenchymal structure can be viewed by stable B-scan or A-scan and, even better, on the grey scale. The principles of applying ultrasounds and for examining results are described together with percutaneous renal punction and nephrostomy guided by ultrasounds. Current applications of echography in congenital and adult diseases are outlined and it is pointed out that the method is simple, non-invasive and precise in differentiating solid from cystic lesions, for appraising solid structures and establishing whether a mass is renal or extrarenal. Experience obtained in evaluating renal lesions and the most typical pictures of these lesions are presented. It is concluded that nephrosonography, independently of renal function, is an excellent method for investigating the kidney, has numerous advantages and is free from danger.