In theory it can be accepted today that the analysis of urinary enzymes has a certain diagnostic value; this enables the diagnosis and observation of kidney damage to be improved without any more drastic measures. Thus it should be possible to recognize new aspects of kidney diseases which cannot be recognized using other, intensive methods. In future urologists and nephrologists should strive to investigate the following problems, relying on adequate documentation of the respective state of the urorenal system: --induction of functional and lesional changes using diagnostic and therapeutic means--evaluation of the effects of medicaments on urinary enzymes--the response of urinary enzymes to infections of the urorenal system--the correlation between the functioning of a transplant and the enzyme pattern in the urine--the search for enzyme markers in patients with cancers of the urogenital tract. The analysis of urinary enzymes is not to be recommended as a method of searching for kidney disease today. Diagnosis through urinary enzymes should not be used as a rule. Our aim for the future should be to use automated biochemical methods with the aid of computer analysis and programming for studies on urinary enzymes.